CN109791371B

CN109791371B - Pattern drawing device and pattern drawing method

Info

Publication number: CN109791371B
Application number: CN201780061213.7A
Authority: CN
Inventors: 加藤正纪; 中山修一
Original assignee: Nikon Corp
Current assignee: Nikon Corp
Priority date: 2016-10-04
Filing date: 2017-05-15
Publication date: 2021-08-06
Anticipated expiration: 2037-05-15
Also published as: TW201826035A; JP6919660B2; KR20190055243A; CN113552778B; KR102414046B1; CN113552778A; WO2018066159A1; TWI736621B; CN109791371A; JPWO2018066159A1

Abstract

A pattern drawing device (EX) is provided with: a position Measuring Unit (MU) for measuring the position of an exposed area on a substrate (P) to be drawn by a plurality of drawing units (Un); a1 st adjustment means (HVP) for adjusting the position of the light Spot (SP) based on each drawing unit (Un) in the 2 nd direction during the movement of the substrate (P) based on the position measured by the position Measurement Unit (MU) so as to reduce the position error of the pattern drawn by each drawing unit (Un) with respect to the exposed area; and a2 nd adjustment means (AOM1) for adjusting the position of the light Spot (SP) based on each drawing unit (Un) in the 2 nd direction with higher responsiveness than the 1 st adjustment means (HVP) during the movement of the substrate (P) in order to reduce the bonding error in the 2 nd direction of the pattern drawn by each drawing unit (Un).

Description

Pattern drawing device and pattern drawing method

Technical Field

The present invention relates to a pattern drawing device and a pattern drawing method for drawing a pattern by scanning a light spot irradiated onto an irradiation target.

Background

As a drawing device using a rotary polygon mirror, for example, there is known an image forming apparatus which includes a plurality of laser exposure units having a polygon mirror, and draws an image by overlapping a part (end) of a scanning area in a main scanning direction in which an exposure light beam is scanned by the polygon mirror so as to be divided into the plurality of laser exposure units, as disclosed in japanese patent laid-open No. 2008-200964. In the apparatus disclosed in japanese patent application laid-open No. 2008-200964, in order to reduce the deviation of the exposure light beam in the sub-scanning direction orthogonal to the main scanning direction due to the difference in the surface inclination of the plurality of reflection surfaces of the polygon mirror in the area overlapped at the end of the scanning area, when the rotation of the polygon mirror of each of the plurality of laser exposure sections is synchronized, the combination of the reflection surfaces of 2 polygon mirrors (the angular phase in the rotation direction) is adjusted so that the deviation in the sub-scanning direction of the image drawn by 1 polygon mirror and the image drawn by the other polygon mirror in the overlapped area is reduced. Further, japanese patent application laid-open No. 2008-200964 discloses that a mechanism for mechanically moving a laser exposure unit including a polygon mirror in a sub-scanning direction is provided to adjust the laser exposure unit so as to reduce the shift of the overlapping area of the images.

Disclosure of Invention

A1 st aspect of the present invention is a pattern drawing device in which a plurality of drawing units that scan a drawing light beam condensed as a light spot on a substrate in a1 st direction to draw a pattern are arranged in the 1 st direction, and the pattern drawn by the plurality of drawing units is joined and drawn in the 1 st direction by movement of the substrate in a2 nd direction intersecting the 1 st direction, the device comprising: a position measuring unit that measures a position of an exposed area on the substrate to be drawn by the plurality of drawing units; a1 st adjustment unit configured to adjust a position of each of the light spots based on the drawing unit in the 2 nd direction during the substrate movement based on the position measured by the position measurement unit so as to reduce a position error of the pattern drawn by the drawing unit with respect to the exposure area; and a2 nd adjusting means for adjusting the position of the light spot by the drawing means in the 2 nd direction with higher responsiveness than the 1 st adjusting means during the movement of the substrate so as to reduce the bonding error in the 2 nd direction of the pattern drawn by the drawing means.

A2 nd aspect of the present invention is a pattern drawing method for scanning a spot of a drawing beam projected from each of a plurality of drawing units arranged in a1 st direction on a substrate in the 1 st direction, moving the substrate in a2 nd direction intersecting the 1 st direction, and bonding a pattern drawn by each of the plurality of drawing units in the 1 st direction for drawing, the method comprising: a measurement step of measuring a position of an exposed area on the substrate by detecting a position of a reference pattern formed on the substrate while the substrate is moving; a1 st adjustment step of adjusting the position of the light spot in the 2 nd direction during the movement of the substrate by the drawing units so that the pattern drawn by the drawing units is aligned with the exposed region based on the position measured in the measurement step; and a2 nd adjustment step of adjusting the position of the light spot by each of the drawing means in the 2 nd direction more finely than in the 1 st adjustment step in order to reduce a bonding error in the 2 nd direction of the pattern drawn by each of the drawing means.

The 3 rd aspect of the present invention is a pattern drawing device including: a rotary polygon mirror that performs one-dimensional scanning in a main scanning direction of a drawing beam intensity-modulated in accordance with a pattern to be drawn on a substrate; and a scanning optical system for converging the one-dimensionally scanned drawing beam as a light spot on the substrate; and drawing a pattern on the substrate by scanning the light spot in the main scanning direction and by relative movement between the substrate and the light spot in a sub-scanning direction intersecting the main scanning direction, the apparatus comprising: a mechanical optical 1-adjustment member that is disposed in an optical path of the drawing beam before entering the rotary polygon mirror or in an optical path of the drawing beam from the rotary polygon mirror to the substrate so as to adjust a position of the spot that is one-dimensionally scanned in the main scanning direction in the sub-scanning direction; and a photoelectric 2 nd adjusting member disposed on an optical path of the drawing beam before the beam enters the rotary polygon mirror and on an optical path immediately before the 1 st adjusting member, for adjusting a position of the spot one-dimensionally scanned in the main scanning direction in the sub-scanning direction.

Drawings

Fig. 1 is a diagram showing a schematic configuration of a device manufacturing system including a pattern exposure apparatus according to embodiment 1 for performing exposure processing on a substrate.

Fig. 2 is a configuration diagram showing a configuration of the exposure apparatus of fig. 1.

Fig. 3 is a detailed view showing a state in which the substrate is wound around the rotary drum shown in fig. 2.

Fig. 4 is a diagram showing a drawing line of a light spot scanned on a substrate and an alignment mark formed on the substrate.

Fig. 5 is a diagram showing an optical configuration of the scanning unit shown in fig. 2.

Fig. 6 is a structural diagram of the beam switching unit shown in fig. 2.

Fig. 7 is a diagram showing a configuration of the light source device shown in fig. 2.

Fig. 8 is a timing chart showing a clock signal generated by a signal generating section in the light source device shown in fig. 7 and a relationship between bit string data and a light beam emitted from the polarization beam splitter.

Fig. 9 is a block diagram showing a configuration of an electric control system of the exposure apparatus shown in fig. 2.

Fig. 10 is a timing chart showing an origin signal output from the origin sensor in the scanning unit shown in fig. 5 and an incidence permission signal generated by the selection element drive control unit shown in fig. 9 based on the origin signal.

Fig. 11 is a block diagram showing a configuration of a signal generating section in the light source device shown in fig. 2.

Fig. 12 is a timing chart showing signals output from each unit of the signal generating unit shown in fig. 11.

Fig. 13A of fig. 13 is a diagram illustrating a pattern drawn when the partial magnification correction is not performed, and fig. 13B of fig. 13 is a diagram illustrating a pattern drawn when the partial magnification correction (reduction) is performed according to the timing chart shown in fig. 12.

Fig. 14 is a diagram showing the configuration of the light beam switching unit according to modification 1 provided in place of the optical element for selection according to embodiment 1.

Fig. 15 is a diagram showing the configuration of the beam switching unit of modification 2 when the optical element for selection in the beam switching unit shown in fig. 6 is replaced with modification 1 of fig. 14.

Fig. 16 is a diagram showing a detailed optical arrangement of a beam phase shifter incorporated in the beam switching unit according to modification 2 shown in fig. 15.

Fig. 17A of fig. 17 shows a prism-shaped photoelectric element used as a modification 3 instead of the selective optical element, and fig. 17B of fig. 17 shows another example of the photoelectric element.

Fig. 18 is a diagram showing in detail the configuration of the wavelength conversion unit in the pulsed light generation unit of the light source device according to embodiment 2.

Fig. 19 is a diagram showing the optical path of the light beam from the light source device to the first optical element for selection in embodiment 2.

Fig. 20 is a diagram showing the optical path from the optical element for selection to the next optical element for selection and the configuration of the drive circuit of the optical element for selection in embodiment 2.

Fig. 21 is a diagram illustrating the selection of the light flux and the displacement of the light flux in the unit-side entrance mirror for selection after the optical element for selection in embodiment 2.

Fig. 22 is a diagram illustrating the operation of the light flux from the polygon mirror to the substrate in embodiment 2.

Fig. 23 is a diagram showing a specific configuration of the scanner unit according to embodiment 3.

Fig. 24A of fig. 24 is a diagram illustrating a case where the position of the light flux is adjusted by the parallel flat plate provided in the scanning unit shown in fig. 23, and a diagram illustrating a state where the incident surface and the output surface of the parallel flat plate which are parallel to each other are at 90 degrees with respect to the center line (principal ray) of the light flux, and fig. 24B of fig. 24 is a diagram illustrating a case where the position of the light flux is adjusted by the parallel flat plate provided in the scanning unit shown in fig. 23, and a diagram illustrating a state where the incident surface and the output surface of the parallel flat plate which are parallel to each other are inclined from 90 degrees with respect to the center line (principal ray) of the light flux.

Fig. 25 is a block diagram showing a schematic configuration of a control device that controls the pattern drawing device according to embodiment 4.

Fig. 26 is a schematic enlarged view showing a state of a light beam in a part of an optical path in the scanning unit (drawing unit) shown in fig. 23.

Fig. 27 is a diagram showing an optical system configuration from the polygon mirror of the scanning unit (drawing unit) shown in fig. 23 to the substrate.

Detailed Description

Preferred embodiments of the pattern drawing device and the pattern drawing method according to aspects of the present invention will be described in detail below with reference to the drawings. Further, the aspects of the present invention are not limited to the embodiments, and include those to which various changes or improvements are applied. That is, the components described below include those which can be easily conceived or substantially similar by a person having ordinary skill in the art to which the invention pertains, and the components described below may be appropriately combined. Various omissions, substitutions, and changes in the components can be made without departing from the spirit of the invention.

[ embodiment 1 ]

Fig. 1 is a diagram showing a schematic configuration of a device manufacturing system 10 including an exposure apparatus EX according to embodiment 1 for performing an exposure process on a substrate (irradiation target) P. In the following description, unless otherwise specified, an XYZ rectangular coordinate system is set with the gravity direction set to the Z direction, and the X direction, the Y direction, and the Z direction are described by arrows shown in the drawings.

The device manufacturing system 10 is a system (substrate processing apparatus) that performs a specific process (such as an exposure process) on a substrate P to manufacture an electronic device. The device manufacturing system 10 is a manufacturing system in which manufacturing lines for manufacturing, for example, a film-shaped color filter, a flexible wiring, a flexible sensor, and the like for a flexible display, a film-shaped touch panel, and a liquid crystal display panel, which are electronic devices, are constructed. Hereinafter, a flexible display will be explained as an electronic device on the premise of a flexible display. Examples of flexible displays include organic EL displays and liquid crystal displays. The device manufacturing system 10 has a so-called Roll-To-Roll (Roll To Roll) configuration as follows: a substrate P is fed from a supply roll FR1 that winds a flexible sheet-like substrate (sheet substrate) P into a roll, various processes are continuously performed on the fed substrate P, and then the substrate P after various processes is wound up by a recovery roll FR 2. The substrate P has a belt-like shape in which the moving direction (transfer direction) of the substrate P is a long side direction (long) and the width direction is a short side direction (short). In embodiment 1, an example is shown in which a film-like substrate P is taken up to a take-up reel FR2 via at least a processing apparatus (1 st processing apparatus) PR1, a processing apparatus (2 nd processing apparatus) PR2, an exposure apparatus (3 rd processing apparatus) EX, a processing apparatus (4 th processing apparatus) PR3, and a processing apparatus (5 th processing apparatus) PR 4.

In embodiment 1, the X direction is a direction (conveyance direction) in which the substrate P is directed from the supply roll FR1 to the recovery roll FR2 in the horizontal plane. The Y direction is a direction orthogonal to the X direction in the horizontal plane, and is a width direction (short bar direction) of the substrate P. The Z direction is a direction (upward direction) orthogonal to the X direction and the Y direction, and is parallel to the direction in which gravity acts.

For example, a resin film or a foil (metal foil) made of a metal such as stainless steel or an alloy is used as the substrate P. As the material of the resin film, for example, at least 1 or more of polyethylene resin, polypropylene resin, polyester resin, ethylene-based copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, and vinyl acetate resin can be used. The thickness or rigidity (young's modulus) of the substrate P may be within a range that does not cause a fold or irreversible wrinkles due to buckling of the substrate P when passing through the transfer path of the device manufacturing system 10. As a base material of the substrate P, a film of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), or the like having a thickness of about 25 to 200 μm is a typical preferable thin substrate.

The substrate P may receive heat in each process performed by the processing apparatus PR1, the processing apparatus PR2, the exposure apparatus EX, the processing apparatus PR3, and the processing apparatus PR4, and therefore, it is preferable to select a substrate P having a material with an insignificant thermal expansion. For example, the thermal expansion coefficient can be suppressed by mixing an inorganic filler into a resin film. The inorganic filler may also be, for example, titanium oxide, zinc oxide, aluminum oxide, or silicon oxide. The substrate P may be a single layer of an extra thin glass having a thickness of about 100 μm manufactured by a float method or the like, or may be a laminate in which the above resin film, foil, or the like is laminated on the extra thin glass.

The flexibility of the substrate P means a property of being able to bend the substrate P without shearing or breaking even if a force of a self-weight is applied to the substrate P. Also, the property of bending by a force of its own weight is included in flexibility. The degree of flexibility varies depending on the material, size, and thickness of the substrate P, the layer structure formed on the substrate P, and the environment such as temperature and humidity. In general, when the substrate P is accurately wound around a member for changing the transport direction, such as various transport rollers and rotary drums, which are provided on the transport path in the device manufacturing system 10 according to embodiment 1, the flexibility range can be defined as long as the substrate P can be smoothly transported without being bent, folded, or broken (cracked or cracked).

The processing apparatus PR1 is a coating apparatus that performs coating processing on the substrate P while conveying the substrate P conveyed from the supply roll FR1 toward the processing apparatus PR2 at a specific speed in a conveyance direction (+ X direction) along the longitudinal direction. The processing apparatus PR1 selectively or uniformly applies the photosensitive functional liquid to the surface of the substrate P. The substrate P coated with the photosensitive functional liquid on the surface thereof is conveyed toward the processing apparatus PR 2.

The processing apparatus PR2 is a drying apparatus that performs a drying process on the substrate P while conveying the substrate P conveyed from the processing apparatus PR1 toward the exposure apparatus EX in a conveyance direction (+ X direction) at a specific speed. The processing apparatus PR2 removes the solvent or water contained in the photosensitive functional liquid by a blower for blowing drying air (warm air) such as hot air or dry air to the surface of the substrate P, an infrared light source, a ceramic heater, or the like, thereby drying the photosensitive functional liquid. Thereby, a film to be a photosensitive functional layer (photosensitive layer) is selectively or uniformly formed on the surface of the substrate P. Further, a photosensitive functional layer may be formed on the surface of the substrate P by attaching the dry film to the surface of the substrate P. In this case, instead of the processing apparatus PR1 and the processing apparatus PR2, a bonding apparatus (processing apparatus) for bonding a dry film to the substrate P may be provided.

Here, the photosensitive functional liquid (layer) is typically a photoresist (liquid or dry film), and examples of the material not requiring development treatment include a photosensitive silane coupling agent (SAM) modified in lyophilicity and lyophobicity in a portion irradiated with ultraviolet light, a photosensitive reducing agent in which a reducing group is plated and exposed in a portion irradiated with ultraviolet light, and the like. When a photosensitive silane coupling agent is used as the photosensitive functional liquid (layer), the pattern portion exposed to ultraviolet light on the substrate P is modified from lyophilic to lyophilic. Therefore, by selectively applying a liquid containing a conductive ink (an ink containing conductive nanoparticles such as silver or copper) or a semiconductor material to the portion having lyophilic properties, a pattern layer which constitutes an electrode of a Thin Film Transistor (TFT) or the like, a semiconductor, or an insulating or connecting wiring can be formed. In the case of using a photosensitive reducing agent as the photosensitive functional liquid (layer), a pattern portion exposed by ultraviolet light on the substrate P is plated with a reducing group and exposed. Therefore, immediately after exposure, the substrate P is immersed in a plating solution containing palladium ions or the like for a fixed time, whereby a pattern layer of palladium is formed (deposited). Such plating treatment is assumed to be an additive (additive) process, and may be assumed to be an etching treatment in a subtractive (reactive) process. In this case, the substrate P to be conveyed to the exposure apparatus EX may be formed by depositing a metal thin film of aluminum (Al), copper (Cu), or the like on the entire surface of a base material, which is PET or PEN, or selectively depositing a photoresist layer thereon. In embodiment 1, a photosensitive reducing agent is used as the photosensitive functional liquid (layer).

The exposure apparatus EX is a processing apparatus that performs exposure processing on the substrate P while conveying the substrate P conveyed from the processing apparatus PR2 in the conveyance direction (+ X direction) at a specific speed toward the processing apparatus PR 3. The exposure apparatus EX irradiates the surface of the substrate P (the surface of the photosensitive functional layer, i.e., the photosensitive surface) with a light pattern corresponding to a pattern for an electronic device (e.g., a pattern of an electrode, a wiring, or the like of a TFT constituting the electronic device). Thereby, a latent image (modified portion) corresponding to the pattern is formed on the photosensitive functional layer.

In embodiment 1, the exposure apparatus EX is a line-scanning type exposure apparatus without using a mask, so-called a raster-scanning type exposure apparatus (pattern writing apparatus). As will be described in detail later, the exposure apparatus EX scans (main-scans) the spot SP of the pulse-shaped beam LB (pulse beam) for exposure one-dimensionally in a specific scanning direction (Y direction) on the irradiated surface (photosensitive surface) of the substrate P while conveying the substrate P in the + X direction (sub-scanning direction), and rapidly modulates (turns on/off) the intensity of the spot SP based on pattern data (drawing data and pattern information). Thereby, a light pattern corresponding to a specific pattern of an electronic device, a circuit, a wiring, or the like is drawn and exposed on the irradiated surface of the substrate P. That is, the sub-scanning of the substrate P and the main scanning of the spot SP cause the spot SP to perform the two-dimensional scanning relative to the irradiated surface of the substrate P, thereby drawing and exposing a specific pattern on the substrate P. Since the substrate P is transported along the transport direction (+ X direction), a plurality of exposure areas W of the exposure pattern by the exposure apparatus EX are provided at a predetermined interval along the longitudinal direction of the substrate P (see fig. 4). Since the electronic device is formed in the exposed region W, the exposed region W is also a device formation region. Further, since the electronic device is configured by overlapping a plurality of pattern layers (layers having patterns formed thereon), patterns corresponding to the respective layers can be exposed by the exposure apparatus EX.

The processing apparatus PR3 is a wet processing apparatus that performs wet processing on the substrate P while conveying the substrate P conveyed from the exposure apparatus EX toward the processing apparatus PR4 in the conveying direction (+ X direction) at a specific speed. In embodiment 1, the processing apparatus PR3 performs plating processing, which is one of wet processing, on the substrate P. That is, the substrate P is immersed in the plating solution stored in the processing bath for a predetermined time. Thereby, a pattern layer corresponding to the latent image is deposited (formed) on the surface of the photosensitive functional layer. That is, a pattern layer is formed by selectively forming a specific material (for example, palladium) on the substrate P according to the difference between the irradiated portion and the non-irradiated portion of the spot SP on the photosensitive functional layer of the substrate P.

In the case of using a photosensitive silane coupling agent as the photosensitive functional layer, a coating treatment or plating treatment of a liquid (for example, a liquid containing conductive ink or the like) as one of wet treatments is performed by the treatment apparatus PR 3. That is, in this case, a pattern layer corresponding to the latent image is also formed on the surface of the photosensitive functional layer. That is, a pattern layer is formed by selectively forming a specific material (for example, conductive ink, palladium, or the like) on the substrate P according to the difference between the irradiated portion and the irradiated portion of the light spot SP of the photosensitive functional layer of the substrate P. When a photoresist is used as the photosensitive functional layer, a developing process, which is one of wet processes, is performed by the processing apparatus PR 3. In this case, a pattern corresponding to the latent image is formed on the photosensitive functional layer (photoresist) by the development treatment.

The processing apparatus PR4 is a cleaning and drying apparatus that cleans and dries the substrate P while conveying the substrate P conveyed from the processing apparatus PR3 toward the take-up reel FR2 in the conveyance direction (+ X direction) at a specific speed. The processing apparatus PR4 cleans the substrate P subjected to the wet processing with pure water, and then dries the substrate P at a glass transition temperature or lower until the water content of the substrate P becomes a specific value or lower.

When a photosensitive silane coupling agent is used as the photosensitive functional layer, the processing apparatus PR4 may be an annealing/drying apparatus that performs an annealing process and a drying process on the substrate P. The annealing treatment is performed by irradiating the substrate P with high-brightness pulsed light from a flash lamp, for example, in order to consolidate the electrical bonding between the nanoparticles contained in the applied conductive ink. When a photoresist is used as the photosensitive functional layer, a processing apparatus (wet processing apparatus) PR5 for performing an etching process and a processing apparatus (cleaning/drying apparatus) PR6 for cleaning/drying the substrate P subjected to the etching process may be provided between the processing apparatus PR4 and the recovery roll FR 2. Thus, when a photoresist is used as the photosensitive functional layer, a pattern layer is formed on the substrate P by performing an etching process. That is, a pattern layer is formed by selectively forming a specific material (for example, aluminum (Al) or copper (Cu)) on the substrate P according to the difference between the irradiated portion and the irradiated portion of the spot SP of the photosensitive functional layer of the substrate P. The processing apparatuses PR5 and PR6 have a function of conveying the substrate P to be conveyed toward the recovery roll FR2 at a specific speed in the conveyance direction (+ X direction). The plurality of processing apparatuses PR1 to PR4 (including the processing apparatuses PR5 and PR6 as necessary) are configured as substrate transfer apparatuses having a function of transferring the substrate P in the + X direction.

Thus, the substrate P subjected to each process is collected by the collection reel FR 2. After at least each process of the

device manufacturing system

10, 1 pattern layer is formed on the substrate P. As described above, the electronic device is constructed by overlapping a plurality of pattern layers, and thus, in order to produce the electronic device, each process of the device manufacturing system 10 shown in fig. 1 must be performed at least 2 times. Therefore, the pattern layer can be laminated by mounting the recovery roll FR2, around which the substrate P is wound, as the supply roll FR1 to another device manufacturing system 10. The above-described operations are repeated to form an electronic device. The processed substrate P is in a state where a plurality of electronic devices are connected at a specific interval along the longitudinal direction of the substrate P. That is, the substrate P serves as a substrate for obtaining a plurality of substrates.

The recovery reel FR2 for recovering the substrate P on which the electronic components are formed in a continuous state may be mounted on a cutting device not shown. The dicing apparatus mounted with the recovery roll FR2 is configured to form a plurality of electronic components in a single piece by dividing (dicing) the processed substrate P into the electronic components (exposed regions W as device forming regions). The substrate P has a dimension in the width direction (direction of short bars) of about 10cm to 2m, and a dimension in the longitudinal direction (direction of long bars) of 10m or more, for example. The size of the substrate P is not limited to the above size.

Fig. 2 is a configuration diagram showing a configuration of the exposure apparatus EX. The exposure apparatus EX is housed in a temperature-controlled room ECV. The temperature controlled chamber ECV is set to a humidity that suppresses a change in shape of the substrate P conveyed therein due to a temperature by maintaining the inside at a specific temperature and a specific humidity, and that takes into account the hygroscopicity of the substrate P and the electrostatic charge generated by the conveyance. The temperature-controlled room ECV is installed on an installation surface E of a manufacturing plant through passive or active vibration-proof units SU1 and SU 2. The vibration isolation units SU1 and SU2 reduce vibration from the installation surface E. The installation surface E may be a floor surface of a factory, or may be an upper surface of an installation base (pedestal) provided on a floor surface exclusively for forming a horizontal surface. The exposure apparatus EX includes at least a

substrate conveyance mechanism

12, 2 light source devices (light sources) LS (LSa, LSb) having the same configuration, a light beam switching unit (including a photoelectric deflection device) BDU, an exposure head (scanning device) 14, a control device 16, a plurality of alignment microscopes AM1m, AM2m (m is 1, 2, 3, 4), and a plurality of encoders ENja, ENjb (j is 1, 2, 3, 4). The control device (control unit) 16 controls each unit of the exposure apparatus EX. The control device 16 includes a computer, a recording medium on which a program is recorded, and the computer executes the program to function as the control device 16 according to embodiment 1.

The substrate transfer mechanism 12 is a part of the substrate transfer apparatus constituting the device manufacturing system 10, and transfers the substrate P transferred from the processing apparatus PR2 at a predetermined speed in the exposure apparatus EX, and then delivers the substrate P at a predetermined speed to the processing apparatus PR 3. The substrate transfer mechanism 12 defines a transfer path for the substrate P transferred in the exposure apparatus EX. The substrate conveyance mechanism 12 includes an edge position controller EPC, a driving roller R1, a dancer roller RT1, a rotary drum (cylindrical drum) DR, a dancer roller RT2, a driving roller R2, and a driving roller R3 in this order from the upstream side (the-X direction side) in the conveyance direction of the substrate P.

The edge position controller EPC adjusts the position in the width direction (Y direction and the short direction of the substrate P) of the substrate P conveyed from the processing apparatus PR 2. That is, the edge position controller EPC moves the substrate P in the width direction so as to adjust the position of the widthwise end (edge) of the substrate P, which is conveyed in a state where a specific tension is applied, in the range of about ± tens μm to several tens μm (allowable range) with respect to the target position. The edge position controller EPC includes a roller on which the substrate P is suspended with a specific tension applied thereto, and an edge sensor (edge detection unit), not shown, that detects the position of an edge (edge) of the substrate P in the width direction. The edge position controller EPC adjusts the position of the substrate P in the width direction by moving the roller of the edge position controller EPC in the Y direction based on the detection signal detected by the edge sensor. The driving rollers (nip rollers) R1 rotate while holding both front and back surfaces of the substrate P conveyed from the edge position controller EPC, and convey the substrate P toward the rotary drum DR. The edge position controller EPC may also be adjusted appropriately to the position in the width direction of the substrate P so that the longitudinal direction of the substrate P wound around the rotary drum DR is always orthogonal to the central axis AXo of the rotary drum DR, and the parallelism between the rotation axis of the roller of the edge position controller EPC and the Y axis may be adjusted appropriately so that the tilt error in the advancing direction of the substrate P is corrected.

The rotary drum DR has a central axis AXo extending in the Y direction and extending in a direction intersecting the direction in which gravity acts, and a cylindrical outer peripheral surface having a constant radius from the central axis AXo. The rotary drum DR supports (holds) a part of the substrate P by bending it in the longitudinal direction into a cylindrical surface shape in accordance with the outer peripheral surface (circumferential surface), and conveys the substrate P in the + X direction by rotating about the central axis AXo. The rotary drum DR is a region (portion) on the substrate P on which the light beam LB (spot SP) from the exposure head 14 is projected, and is supported by the outer peripheral surface thereof. The rotary drum DR supports (holds in close contact with) the substrate P from the side (back side) opposite to the side on which the electronic components are formed (the side on which the photosensitive surface is formed). On both sides of the rotary drum DR in the Y direction, long rods Sft supported by annular bearings so that the rotary drum DR rotates about the center shaft AXo are provided. The long bar Sft is rotated around the center shaft AXo at a constant rotational speed by torque applied from a not-shown rotation drive source (e.g., a motor, a reduction mechanism, etc.) controlled by the control device 16. For convenience, a plane including the central axis AXo and parallel to the YZ plane is referred to as a central plane Poc.

The driving rollers (nip rollers) R2 and R3 are disposed at a predetermined interval along the conveyance direction (+ X direction) of the substrate P, and apply a predetermined slack (play) to the substrate P after exposure. The driving rollers R2 and R3 rotate while holding both front and back surfaces of the substrate P, and convey the substrate P toward the processing apparatus PR3, similarly to the driving roller R1. The tension adjusting rollers RT1 and RT2 are biased in the-Z direction, and apply a predetermined tension in the longitudinal direction to the substrate P wound around and supported by the rotary drum DR. Thereby, the tension in the longitudinal direction applied to the substrate P hung on the rotary drum DR is stabilized within a specific range. The control device 16 rotates the driving rollers R1 to R3 by controlling a not-shown rotation driving source (e.g., a motor, a reducer, or the like). The rotation axes of the driving rollers R1 to R3 and the rotation axes of the tension adjusting rollers RT1 and RT2 are parallel to the central axis AXo of the rotary drum DR.

The light source device LS (LSa, LSb) generates and emits a pulse-shaped light beam (pulse beam, pulsed light, laser light) LB. The light beam LB is ultraviolet light having a peak wavelength in a wavelength band of 370nm or less, and the emission frequency (oscillation frequency, specific frequency) of the light beam LB is Fa. The light beam LB emitted from the light source device LS (LSa, LSb) enters the exposure head 14 through the beam switching portion BDU. The light source means LS (LSa, LSb) emits light at a light emission frequency Fa and emits a light beam LB in accordance with the control of the control means 16. The configuration of the light source device LS (LSa, LSb) will be described in detail below, and in embodiment 1, the light source device is configured by a semiconductor laser element that generates pulsed light in the infrared wavelength range, an optical fiber amplifier, a wavelength conversion element (harmonic generation element) that converts the amplified pulsed light in the infrared wavelength range into pulsed light in the ultraviolet wavelength range, and the like, and is configured as a fiber amplifier laser light source (harmonic laser light source) that obtains ultraviolet pulsed light with high brightness having an oscillation frequency Fa of several hundred MHz and an emission time of 1 pulsed light of about picoseconds. In order to distinguish the light beam LB from the light source device LSa from the light beam LB from the light source device LSb, the light beam LB from the light source device LSa may be represented by LBa, and the light beam LB from the light source device LSb may be represented by LBb.

The light beam switching unit BDU is configured to make the light beam LB (LBa, LBb) from the 2 light source devices LS (LSa, LSb) enter 2 scanning units Un of the plurality of scanning units Un (where n is 1, 2, …, 6) constituting the exposure head 14, and to switch the scanning unit Un on which the light beam LB (LBa, LBb) enters. In detail, the light beam switching section BDU makes the light beam LBa from the light source device LSa incident on 1 scan cell Un among the 3 scan cells U1 to U3, and makes the light beam LBb from the light source device LSb incident on 1 scan cell Un among the 3 scan cells U4 to U6. The beam switching unit BDU switches the scanning unit Un into which the light beam LBa is incident among the scanning units U1 to U3, and switches the scanning unit Un into which the light beam LBb is incident among the scanning units U4 to U6.

The beam switching unit BDU switches the scanning unit Un on which the light beams LBa and LBb are incident so that the light beam LBn enters the scanning unit (drawing unit) Un that scans the spot SP. That is, the light beam switching unit BDU causes the light beam LBa from the light source device LSa to enter 1 scanning unit Un of the scanning units U1 to U3, which scans the light spot SP. Similarly, the light beam switching unit BDU causes the light beam LBb from the light source device LSb to enter 1 scanning unit Un of the scanning units U4 to U6, which scans the light spot SP. The beam switching unit BDU will be described in detail below. Further, the scanning units U1 to U3 switch the scanning unit Un that scans the light spot SP in the order of U1 → U2 → U3, and the scanning units U4 to U6 switch the scanning unit Un that scans the light spot SP in the order of U4 → U5 → U6. The above-described configuration of the light beam switching unit BDU and the light source device LS (LSa, LSb) is disclosed in, for example, international publication No. 2015/166910, and will be described in detail below with reference to fig. 6 and 7.

The exposure head 14 is a so-called multi-beam type exposure head in which a plurality of scanning units Un (U1 to U6) having the same configuration are arranged. The exposure head 14 draws a pattern on a part of the substrate P supported by the outer circumferential surface (circumferential surface) of the rotary drum DR by a plurality of scanning units Un (U1 to U6). Since the exposure head 14 repeatedly performs pattern exposure for the electronic device on the substrate P, a plurality of exposed regions (electronic device forming regions) W of the exposure pattern are provided at a predetermined interval along the longitudinal direction of the substrate P (see fig. 4). The plurality of scanning units Un (U1-U6) are arranged in a specific arrangement relationship. The plurality of scanning units Un (U1 to U6) are arranged in 2 rows in the conveyance direction of the substrate P with the center plane Poc therebetween. The odd-numbered scanning units U1, U3, and U5 are disposed upstream (on the (-X direction side) in the conveyance direction of the substrate P with respect to the center plane Poc, and are disposed in 1 row at a predetermined interval in the Y direction. The even-numbered scan units U2, U4, and U6 are disposed on the downstream side (+ X direction side) of the center plane Poc in the conveyance direction of the substrate P, and are disposed in 1 row at a predetermined interval in the Y direction. The odd-numbered scan cells U1, U3, and U5 and the even-numbered scan cells U2, U4, and U6 are arranged symmetrically with respect to the center plane Poc when viewed in the XZ plane.

Each of the scanning units Un (U1 to U6) projects the light beam LB from the light source LS (LSa, LSb) so as to converge on the irradiated surface of the substrate P to form a spot SP, and scans the spot SP one-dimensionally by a rotating polygon mirror PM (see fig. 5). The spot SP is scanned one-dimensionally on the irradiation surface of the substrate P by the polygon mirror (deflecting member) PM of each of the scanning units Un (U1 to U6). By scanning the spot SP, a drawing line (scanning line) SLn (n is 1, 2, …, or 6) which draws a straight line corresponding to a pattern of 1 line is defined on the substrate P (on the surface to be irradiated of the substrate P). The configuration of the scanning unit Un will be described in detail below.

The scanning unit U1 scans the light spot SP along the scanning line SL1, and similarly, the scanning units U2 to U6 scan the light spot SP along the scanning lines SL2 to SL 6. As shown in fig. 3 and 4, the drawing lines SLn (SL1 to SL6) of the plurality of scanning units Un (U1 to U6) are set so as not to be separated from each other and joined in the Y direction (the width direction of the substrate P, the main scanning direction). The light beam LB from the light source device LS (LSa, LSb) that enters the scanning unit Un via the light beam switching unit BDU is sometimes represented as LBn. Further, LB1 may denote a light beam LBn incident on the scanning unit U1, and LB2 to LB6 may denote a light beam LBn incident on the scanning units U2 to U6. The drawing lines SLn (SL1 to SL6) indicate scanning trajectories of the spots SP of the light beams LBn (LB1 to LB6) scanned by the scanning units Un (U1 to U6). The light flux LBn incident on the scanning unit Un may be a linearly polarized light (P-polarized light or S-polarized light) polarized in a specific direction, and in embodiment 1, is a P-polarized light flux.

As shown in fig. 4, each of the scanning units Un (U1 to U6) shares a scanning region so that the plurality of scanning units Un (U1 to U6) collectively cover the entire width direction of the exposure region W. Thus, each of the scanning units Un (U1 to U6) can draw a pattern for each of a plurality of regions (drawing ranges) divided in the width direction of the substrate P. For example, if the Y-direction scanning length (the length of the drawing line SLn) of 1 scan cell Un is set to about 20 to 60mm, the Y-direction width that can be drawn is increased to about 120 to 360mm by arranging 3 scan cells Un in the Y direction, which are 3 scan cells U1, U3, and U5 in odd number, and 3 scan cells U2, U4, and U6 in even number, that is, 6 scan cells Un in total. The lengths (the lengths of the drawing ranges) of the drawing lines SLn (SL1 to SL6) are basically the same. That is, the scanning distances of the spot SP of the light beam LBn scanned along the scanning lines SL1 to SL6 are set to be the same in principle. In addition, when the width of the exposed area W is to be increased, the length of the scanning line SLn itself may be increased or the number of scanning units Un arranged in the Y direction may be increased.

Each of the actual scanning lines SLn (SL1 to SL6) is set to be slightly shorter than the maximum length (maximum scanning length) that the spot SP can actually scan on the irradiation surface. For example, if the scanning length of the drawing line SLn capable of pattern drawing is 30mm when the drawing magnification in the main scanning direction (Y direction) is an initial value (no magnification correction), the maximum scanning length of the spot SP on the irradiated surface is set to be about 31mm with a margin of about 0.5mm on the drawing start point (scanning start point) side and the drawing end point (scanning end point) side of the drawing line SLn, respectively. By setting in this manner, the position of the drawing line SLn of 30mm can be finely adjusted in the main scanning direction or the drawing magnification can be finely adjusted within the range of the maximum scanning length 31mm of the spot SP. The maximum scanning length of the spot SP is not limited to 31mm, and is mainly determined by the aperture of an f θ lens FT (see fig. 5) provided behind a polygon mirror (rotary polygon mirror) PM in the scanning unit Un.

The plurality of drawing lines SLn (SL1 to SL6) are arranged in 2 lines in the circumferential direction of the rotary drum DR with the center plane Poc therebetween. The odd-numbered drawing lines SL1, SL3, and SL5 are located on the irradiated surface of the substrate P on the upstream side (the (-X direction side) in the conveyance direction of the substrate P with respect to the central plane Poc. The even-numbered drawing lines SL2, SL4, and SL6 are located on the irradiated surface of the substrate P on the downstream side (+ X direction side) in the conveyance direction of the substrate P with respect to the central plane Poc. The drawing lines SL1 to SL6 are substantially parallel to the width direction of the substrate P, i.e., the central axis AXo of the rotary drum DR.

The scanning lines SL1, SL3, and SL5 are arranged in 1 line at a predetermined interval in the width direction (main scanning direction) of the substrate P. Similarly, the drawing lines SL2, SL4, and SL6 are arranged linearly in 1 line at a predetermined interval in the width direction (main scanning direction) of the substrate P. At this time, the drawing line SL2 is disposed between the drawing line SL1 and the drawing line SL3 in the width direction of the substrate P. Similarly, the drawing line SL3 is disposed between the drawing line SL2 and the drawing line SL4 in the width direction of the substrate P. The drawing line SL4 is disposed between the drawing line SL3 and the drawing line SL5 in the width direction of the substrate P, and the drawing line SL5 is disposed between the drawing line SL4 and the drawing line SL6 in the width direction of the substrate P. In this way, the plurality of drawing lines SLn (SL1 to SL6) are arranged to be shifted from each other in the Y direction (main scanning direction).

The main scanning directions of the spots SP of the light beams LB1, LB3, LB5 scanned along the odd-numbered scanning lines SL1, SL3, SL5 are one-dimensional directions and the same direction. The main scanning directions of the spots SP of the light beams LB2, LB4, LB6 scanned along the even-numbered scanning lines SL2, SL4, SL6 are one-dimensional directions and the same direction. The main scanning direction of the spot SP of the light beams LB1, LB3, LB5 scanned along the drawing lines SL1, SL3, SL5 and the main scanning direction of the spot SP of the light beams LB2, LB4, LB6 scanned along the drawing lines SL2, SL4, SL6 may be opposite to each other. In embodiment 1, the main scanning direction of the spot SP of the light beams LB1, LB3, LB5 scanned along the scanning lines SL1, SL3, SL5 is the-Y direction. The main scanning direction of the spot SP of the light beams LB2, LB4, LB6 scanned along the scanning lines SL2, SL4, SL6 is the + Y direction. Accordingly, the ends of the drawing lines SL1, SL3, and SL5 on the drawing start point side are adjacent to or partially overlap the ends of the drawing lines SL2, SL4, and SL6 on the drawing start point side in the Y direction. The ends of the drawing lines SL3 and SL5 on the drawing end point side are adjacent to or partially overlap the ends of the drawing lines SL2 and SL4 on the drawing end point side in the Y direction. When the drawing lines SLn are arranged so that the ends of the drawing lines SLn adjacent in the Y direction partially overlap each other, for example, it is preferable that the drawing start point or the drawing end point overlap each other in the Y direction within a range of several percent or less with respect to the length of each drawing line SLn. The joining of the trace lines SLn in the Y direction means that the ends of the trace lines SLn are adjacent to each other (closely attached) or partially overlap each other in the Y direction.

The width of the scanning line SLn in the sub-scanning direction (the dimension in the X direction) is a thickness corresponding to the size (diameter) of the spot SP. For example, when the size (dimension) φ of the spot SP is 3 μm, the width of the drawing line SLn is also 3 μm. The spot SP may be projected along the drawing line SLn so as to overlap with a predetermined length (for example, 1/2 corresponding to the size Φ of the spot SP). When the drawing lines SLn (for example, the drawing lines SL1 and SL2) adjacent to each other in the Y direction are joined to each other, a specific length (for example, 1/2 of the size Φ of the light spot SP) may be overlapped with each other.

In the case of embodiment 1, since the light beams LB (LBa, LBb) from the light source devices LS (LSa, LSb) are pulsed light, the spot SP projected on the scanning line SLn during the main scanning is dispersed according to the oscillation frequency Fa (for example, 400MHz) of the light beams LB (LBa, LBb). Therefore, it is necessary to overlap the spot SP projected by the 1 pulse light of the beam LB and the spot SP projected by the next 1 pulse light in the main scanning direction. The amount of overlap is set in accordance with the size φ of the spot SP, the scanning speed (speed of main scanning) Vs of the spot SP, and the oscillation frequency Fa of the light beam LB. The effective size φ of the spot SP is determined at 1/e2 (or 1/2) of the peak intensity of the spot SP when the intensity distribution of the spot SP is approximated by a Gaussian distribution. In embodiment 1, the scanning speed Vs and the oscillation frequency Fa of the spot SP are set so that the spot SP overlaps with the effective size (size) Φ × 1/2. Therefore, the projection interval of the spot SP in the main scanning direction becomes Φ/2. Therefore, it is preferable to set the substrate P to move by a distance of approximately 1/2 of the effective size Φ of the spot SP between 1 scan and the next scan of the spot SP along the drawing line SLn in the sub-scanning direction (the direction orthogonal to the drawing line SLn). The amount of exposure to the photosensitive functional layer on the substrate P can be set by adjusting the peak value of the light beam LB (pulsed light), but when the amount of exposure is to be increased in a situation where the intensity of the light beam LB cannot be increased, the amount of overlap in the main scanning direction or the sub-scanning direction of the light spot SP may be increased by any of a decrease in the scanning speed Vs in the main scanning direction of the light spot SP, an increase in the oscillation frequency Fa of the light beam LB, a decrease in the conveyance speed Vt in the sub-scanning direction of the substrate P, and the like. The scanning speed Vs in the main scanning direction of the spot SP is accelerated in proportion to the rotation number (rotation speed Vp) of the polygon mirror PM.

Each of the scanning units Un (U1 to U6) irradiates each of the light beams LBn toward the substrate P so that each of the light beams LBn advances toward the central axis AXo of the rotating drum DR in at least the XZ plane. Thus, the optical path (beam center axis) of the light beam LBn that advances from each scanning unit Un (U1 to U6) toward the substrate P is parallel to the normal line of the irradiated surface of the substrate P in the XZ plane. Each of the scanning units Un (U1 to U6) irradiates the substrate P with the light beam LBn so that the light beam LBn irradiating the drawing line SLn (SL1 to SL6) is perpendicular to the irradiated surface of the substrate P in a plane parallel to the YZ plane. That is, the light beam LBn (LB1 to LB6) projected onto the substrate P is scanned in the main scanning direction of the spot SP on the irradiated surface in a telecentric state. Here, a line (or also referred to as an optical axis) passing through each midpoint of the specific drawing lines SLn (SL1 to SL6) defined by the scanning units Un (U1 to U6) and perpendicular to the surface to be irradiated of the substrate P is referred to as an irradiation central axis Len (Le1 to Le 6).

The irradiation central axes Len (Le1 to Le6) are lines connecting the drawing lines SL1 to SL6 and the central axis AXo in the XZ plane. The irradiation central axes Le1, Le3, Le5 of the odd-numbered scanning units U1, U3, U5 are in the same direction in the XZ plane, and the irradiation central axes Le2, Le4, Le6 of the even-numbered scanning units U2, U4, U6 are in the same direction in the XZ plane. The irradiation center axes Le1, Le3, Le5 and the irradiation center axes Le2, Le4, Le6 are set so that the angles thereof are ± θ 1 with respect to the center plane Poc in the XZ plane (see fig. 2).

The alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) shown in fig. 2 are ones for detecting the alignment marks MKm (MK1 to MK4) formed on the substrate P shown in fig. 4, and are provided in plural numbers (4 in the present embodiment 1) along the Y direction. The plurality of alignment marks MKm (MK1 to MK4) are reference marks for aligning (aligning) a specific pattern drawn on the exposure area W on the irradiated surface of the substrate P with respect to the substrate P. The alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) detect alignment marks MKm (MK1 to MK4) on the substrate P supported by the outer circumferential surface (circumferential surface) of the rotary drum DR. The alignment microscopes AM1m (AM11 to AM14) are provided on the upstream side (the (-X direction side) in the substrate P conveyance direction from the irradiated region (the region surrounded by the drawing lines SL1 to SL6) on the substrate P based on the spot SP of the light beam LBn (LB1 to LB6) from the exposure head 14. The alignment microscopes AM2m (AM21 to AM24) are provided on the downstream side (+ X direction side) in the substrate P conveyance direction of the irradiated region (region surrounded by the drawing lines SL1 to SL6) on the substrate P from the spot SP of the light beam LBn (LB1 to LB6) from the exposure head 14.

The alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) have: a light source for projecting illumination light for alignment onto the substrate P; an observation optical system (including an objective lens) that obtains an enlarged image of a local region (observation region) Vw1m (Vw11 to Vw14) and Vw2m (Vw21 to Vw24) including the alignment mark MKm on the surface of the substrate P; and an image pickup device such as a CCD or a CMOS, which picks up the magnified image with a high-speed shutter according to a transport speed Vt of the substrate P while the substrate P is moving in the transport direction. The image pickup signals (image data) picked up by the alignment microscopes AM1m (AM11 to AM14) and AM2m (AM21 to AM24) are transmitted to the control device 16. The mark position detection unit 106 (see fig. 9) of the controller 16 performs image analysis of the plurality of transmitted imaging signals to detect the positions (mark position information) of the alignment marks MKm (MK1 to MK4) on the substrate P. The illumination light for alignment is light in a wavelength region having little sensitivity to the photosensitive functional layer on the substrate P, for example, light having a wavelength of about 500 to 800 nm.

A plurality of alignment marks MK 1-MK 4 are provided around each exposed area W. The alignment marks MK1, MK4 are formed at regular intervals Dh along the longitudinal direction of the substrate P on both sides of the exposed region W in the width direction of the substrate P. Alignment mark MK1 is formed on the-Y direction side in the width direction of substrate P, and alignment mark MK4 is formed on the + Y direction side in the width direction of substrate P. The alignment marks MK1 and MK4 are arranged so as to be at the same position in the longitudinal direction (X direction) of the substrate P in a state where the substrate P is not subjected to a large tension or deformed by a thermal process. Further, alignment marks MK2, MK3 are blank portions formed between alignment mark MK1 and alignment mark MK4 along the width direction (short bar direction) of substrate P, and on the + X direction side and the-X direction side of exposed region W. Alignment marks MK2, MK3 are formed between exposed area W and exposed area W. Alignment mark MK2 is formed on the-Y direction side in the width direction of substrate P, and alignment mark MK3 is formed on the + Y direction side of substrate P.

Further, the distance between alignment mark MK1 arranged at the end on the-Y direction side of substrate P and alignment mark MK2 in the Y direction, the distance between alignment mark MK2 in the blank region and alignment mark MK3 in the Y direction, and the distance between alignment mark MK4 arranged at the end on the + Y direction side of substrate P and alignment mark MK3 in the Y direction are all set to the same distance. The alignment marks MKm (MK1 MK4) may also be formed during the formation of layer 1 pattern layer. For example, when the pattern of the layer 1 is exposed, the pattern for the alignment mark may be exposed also around the exposed region W of the exposure pattern. Furthermore, the alignment mark MKm may also be formed in the exposed area W. For example, the mask may be formed along the contour of the exposed area W in the exposed area W. In addition, a pattern portion at a specific position or a portion having a specific shape in the pattern of the electronic component formed in the exposure field W may be used as the alignment mark MKm.

As shown in fig. 4, the alignment microscopes AM11 and AM21 are arranged to capture alignment marks MK1 present in observation regions (detection regions) Vw11 and Vw21 of the objective lens. Similarly, alignment microscopes AM12 to AM14 and AM22 to AM24 are arranged to capture alignment marks MK2 to MK4 existing in observation regions Vw12 to Vw14 and Vw22 to Vw24 of the objective lens. Therefore, the alignment microscopes AM11 to AM14 and AM21 to AM24 are provided along the width direction of the substrate P in the order of AM11 to AM14 and AM21 to AM24 from the-Y direction side of the substrate P in accordance with the positions of the alignment marks MK1 to MK 4. In fig. 3, the observation region Vw2m (Vw21 to Vw24) of the alignment microscope AM2m (AM21 to AM24) is not shown.

The alignment microscopes AM1m (AM11 to AM14) are provided so that the distance between the exposure position (the drawing lines SL1 to SL6) and the observation region Vw1m (Vw11 to Vw14) in the X direction is shorter than the length of the exposure region W in the X direction. Similarly, the alignment microscopes AM2m (AM21 to AM24) are provided so that the distance between the exposure position (drawn lines SL1 to SL6) and the observation region Vw2m (Vw21 to Vw24) in the X direction is shorter than the length of the exposure region W in the X direction. The number of alignment microscopes AM1m and AM2m provided in the Y direction may be changed according to the number of alignment marks MKm formed in the width direction of the substrate P. The size of the observation regions Vw1m (Vw11 to Vw14) and Vw2m (Vw21 to Vw24) on the irradiated surface of the substrate P is set in accordance with the size of the alignment marks MK1 to MK4 or the alignment accuracy (position measurement accuracy), and is set to a size of about 100 to 500 μm square.

As shown in fig. 3, scale portions SDa, SDb having a scale and formed in a ring shape over the entire circumferential direction of the outer circumferential surface of the rotary drum DR are provided at both end portions of the rotary drum DR. The scale portions SDa and SDb are diffraction gratings on which concave or convex grating lines are formed at a constant pitch (for example, 20 μm) in the circumferential direction of the outer peripheral surface of the rotary drum DR, and are formed as incremental scales. The scales SDa, SDb rotate around the central axis AXo integrally with the rotary drum DR. A plurality of encoders ENja and ENjb (j is 1, 2, 3, and 4) as scale reading heads for reading the scale units SDa and SDb are provided so as to face the scale units SDa and SDb (see fig. 2 and 3). In fig. 3, the encoders EN4a and EN4b are not shown.

The encoders ENja, ENjb optically detect the rotational angle position of the rotary drum DR. 4 encoders ENja (EN1a, EN2a, EN3a, EN4a) are provided facing the scale portion SDa provided at the end of the rotary drum DR on the-Y direction side. Similarly, 4 encoders ENjb (EN1b, EN2b, EN3b, and EN4b) are provided so as to face the scale portion SDb provided at the end of the rotary drum DR on the + Y direction side.

The encoders EN1a and EN1b are disposed upstream (on the (-X direction side) of the center plane Poc in the conveyance direction of the substrate P, and are disposed on the set orientation line Lx1 (see fig. 2 and 3). The set azimuth line Lx1 is a line connecting the projection positions (reading positions) of the light beams for measurement by the encoders EN1a, EN1b on the scales SDa, SDb and the central axis AXo in the XZ plane. The azimuth line Lx1 is a line connecting the observation region Vw1m (Vw11 to Vw14) of each alignment microscope AM1m (AM11 to AM14) to the central axis AXo in the XZ plane. That is, the alignment microscopes AM1m (AM11 to AM14) are also arranged on the installation azimuth line Lx 1.

The encoders EN2a, EN2b are provided upstream (on the (-X direction side) in the substrate P conveyance direction with respect to the center plane Poc, and are provided further downstream (on the + X direction side) in the substrate P conveyance direction than the encoders EN1a, EN1 b. The encoders EN2a and EN2b are disposed on the set square line Lx2 (see fig. 2 and 3). The set azimuth line Lx2 is a line connecting the projection positions (reading positions) of the light beams for measurement by the encoders EN2a, EN2b on the scales SDa, SDb and the central axis AXo in the XZ plane. The installation direction line Lx2 is overlapped with the irradiation center axes Le1, Le3, Le5 at the same angular position in the XZ plane.

The encoders EN3a, EN3b are disposed on the downstream side (+ X direction side) of the center plane Poc in the conveyance direction of the substrate P, and are disposed on the set orientation line Lx3 (see fig. 2 and 3). The set azimuth line Lx3 is a line connecting the projection positions (reading positions) of the light beams for measurement by the encoders EN3a, EN3b on the scales SDa, SDb and the central axis AXo in the XZ plane. The installation direction line Lx3 is overlapped with the irradiation center axes Le2, Le4, Le6 at the same angular position in the XZ plane. Therefore, the set azimuth line Lx2 and the set azimuth line Lx3 are set so that the angle with respect to the center plane Poc in the XZ plane becomes ± θ 1 (see fig. 2).

The encoders EN4a, EN4b are provided on the downstream side (+ X direction side) of the encoders EN3a, EN3b in the conveyance direction of the substrate P, and are disposed on the set orientation line Lx4 (see fig. 2). The set azimuth line Lx4 is a line connecting the projection positions (reading positions) of the light beams for measurement by the encoders EN4a, EN4b on the scales SDa, SDb and the central axis AXo in the XZ plane. The azimuth line Lx4 is a line connecting the observation region Vw2m (Vw21 to Vw24) of each alignment microscope AM2m (AM21 to AM24) to the central axis AXo in the XZ plane. That is, the alignment microscopes AM2m (AM21 to AM24) are also arranged on the installation azimuth line Lx 4. The set azimuth line Lx1 and the set azimuth line Lx4 are set so that an angle of ± θ 2 with respect to the center plane Poc in the XZ plane (see fig. 2).

The encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b) project measuring light beams toward the scale parts SDa and SDb, and photoelectrically detect reflected light beams (diffracted light) thereof, thereby outputting detection signals as pulse signals to the controller 16. The rotational position detecting unit 108 (see fig. 9) of the control device 16 counts the detection signals (pulse signals) thereof to measure the rotational angle position and angular change of the rotating drum DR with a submicron resolution. The conveyance speed Vt of the substrate P can also be measured from the change in the angle of the rotary drum DR. The rotational position detector 108 counts the detection signals from the encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b), respectively.

Specifically, the rotational position detector 108 includes a plurality of counter circuits CNja (CN1a to CN4a) and CNjb (CN1b to CN4 b). The counter circuit CN1a counts the detection signal from the encoder EN1a, and the counter circuit CN1b counts the detection signal from the encoder EN1 b. Similarly, the counter circuits CN2a to CN4a and CN2b to CN4b count detection signals from the encoders EN2a to EN4a and EN2b to EN4 b. Each of the counter circuits CNja (CN1a to CN4a) and CNjb (CN1b to CN4b) resets the count value corresponding to the encoder ENja or ENjb that has detected the origin mark ZZ to 0 when the encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b) detect the origin mark (origin pattern) ZZ shown in fig. 3 formed in a part of the scale portions SDa and SDb in the circumferential direction.

Any one of the count values of the counter circuits CN1a, CN1b or the average value thereof is used as the rotation angle position of the rotary drum DR on the set orientation line Lx1, and any one of the count values of the counter circuits CN2a, CN2b or the average value thereof is used as the rotation angle position of the rotary drum DR on the set orientation line Lx 2. Likewise, any one of the count values or the average value of the counter circuits CN3a, CN3b is used as the rotation angle position of the rotary drum DR on the set orientation line Lx3, and any one of the count values or the average value of the counter circuits CN4a, CN4b is used as the rotation angle position of the rotary drum DR on the set orientation line Lx 4. Note that, the counter circuits CN1a and CN1b basically have the same count value except that the rotary drum DR is eccentrically rotated with respect to the central shaft AXo due to a manufacturing error of the rotary drum DR, or the like. Similarly, the count values of the counter circuits CN2a and CN2b are the same, and the count values of the counter circuits CN3a and CN3b and the count values of the counter circuits CN4a and CN4b are the same, respectively.

As described above, alignment microscopes AM1m (AM11 to AM14) and encoders EN1a and EN1b are disposed on installation azimuth line Lx1, and alignment microscopes AM2m (AM21 to AM24) and encoders EN4a and EN4b are disposed on installation azimuth line Lx 4. Therefore, the position of the substrate P on the installation position line Lx1 can be measured with high accuracy from the position detection of the alignment mark MKm (MK1 to MK4) by the image analysis of the mark position detection unit 106 based on the plurality of imaging signals captured by the plurality of alignment microscopes AM1m (AM11 to AM14) and the information (based on the count values of the encoders EN1a and EN1 b) of the rotational angle position of the rotary drum DR at the moment captured by the alignment microscope AM1 m. Similarly, the position of the substrate P on the installation position line Lx4 can be measured with high accuracy from the position detection of the alignment mark MKm (MK1 to MK4) by the image analysis of the mark position detection unit 106 based on the plurality of imaging signals captured by the plurality of alignment microscopes AM2m (AM21 to AM24) and the information of the rotational angle position of the rotary drum DR at the moment captured by the alignment microscope AM2m (based on the count values of the encoders EN4a and EN4 b).

The count values of the detection signals from the encoders EN1a, EN1b, the count values of the detection signals from the encoders EN2a, EN2b, the count values of the detection signals from the encoders EN3a, EN3b, and the count values of the detection signals from the encoders EN4a, EN4b are reset to zero at the moment when the origin flag ZZ is detected by each of the encoders ENja, ENjb. Therefore, when the position on installation orientation line Lx1 of substrate P wound around rotary drum DR when the count value by encoders EN1a, EN1b is the 1 st value (for example, 100) is set as the 1 st position, the count value by encoders EN2a, EN2b becomes the 1 st value (for example, 100) when the 1 st position on substrate P is conveyed to the position on installation orientation line Lx2 (the positions of drawn lines SL1, SL3, SL 5). Similarly, when the substrate P is transported from the 1 st position to a position on the set orientation line Lx3 (position of the drawn lines SL2, SL4, and SL6), the count value of the detection signal by the encoders EN3a and EN3b becomes the 1 st value (for example, 100). Similarly, when the substrate P is transported from the 1 st position to the position on the set azimuth line Lx4, the count value based on the detection signals of the encoders EN4a and EN4b becomes the 1 st value (for example, 100).

The substrate P is wound inside the scale portions SDa and SDb at both ends of the rotary drum DR. In fig. 2, the radius from the central axis AXo of the outer peripheral surface of each of the scale sections SDa and SDb is set to be smaller than the radius from the central axis AXo of the outer peripheral surface of the rotary drum DR. However, as shown in fig. 3, the outer peripheral surfaces of the scale portions SDa, SDb may be flush with the outer peripheral surface of the substrate P wound around the rotary drum DR. That is, the radius (distance) from the central axis AXo of the outer peripheral surface of the scale sections SDa, SDb may be set to be the same as the radius (distance) from the central axis AXo of the outer peripheral surface (irradiated surface) of the substrate P wound around the rotary drum DR. Accordingly, the encoders ENja (EN1a to EN4a) and ENjb (EN1b to EN4b) can detect the scale portions SDa and SDb at the same radial position as the irradiated surface of the substrate P wound around the rotary drum DR. Therefore, abbe errors caused by the difference between the measurement positions of the encoders ENja and ENjb and the processing positions (drawn lines SL1 to SL6) in the radial direction of the rotary drum DR can be reduced.

However, since the thickness of the substrate P as the irradiation object is ten μm to several hundred μm and is greatly different, it is difficult to always make the radius of the outer peripheral surface of the scale portions SDa and SDb equal to the radius of the outer peripheral surface of the substrate P wound around the rotary drum DR. Therefore, in the case of the scale portions SDa, SDb shown in fig. 3, the radius of the outer peripheral surface (scale surface) thereof is set to match the radius of the outer peripheral surface of the rotary drum DR. Further, the scale portions SDa, SDb may be formed by separate disks, and the disks (scale disks) may be coaxially attached to the long rod Sft of the rotary drum DR. In this case, it is also preferable that the radius of the outer peripheral surface (scale surface) of the scale disk and the radius of the outer peripheral surface of the rotary drum DR are matched to each other to such an extent that the abbe error is controlled within the allowable value.

From the above, the control device 16 determines the start position of the writing exposure of the exposure area W in the longitudinal direction (X direction) of the substrate P based on the position of the alignment mark MKm (MK1 to MK4) on the substrate P detected by the alignment microscope AM1m (AM11 to AM14) and the count values (any one or the average of the count values of the counter circuits CN1a and CN1 b) by the encoders EN1a and EN1 b. Since the length of the exposure area W in the X direction is known in advance, the controller 16 determines the start position of the drawing exposure every time a specific number of alignment marks MKm (MK1 to MK4) are detected. When the count value by the encoders EN1a, EN1b at the time of determining the exposure start position is set to the 1 st value (for example, 100), and when the count value by the encoders EN2a, EN2b is set to the 1 st value (for example, 100), the start position of the drawing exposure of the exposure field W in the longitudinal direction of the substrate P is located on the drawing lines SL1, SL3, SL 5. Accordingly, the scanning units U1, U3, U5 can start scanning of the spot SP according to the count values of the encoders EN2a, EN2 b. When the count value by the encoders EN3a, EN3b is the 1 st value (for example, 100), the start position of the drawing exposure of the exposure field W in the longitudinal direction of the substrate P is located on the drawing lines SL2, SL4, and SL 6. Accordingly, the scanning units U2, U4, U6 can start scanning of the spot SP according to the count values of the encoders EN3a, EN3 b.

In fig. 2, the substrate P is normally conveyed while being in close contact with the rotary drum DR while being rotated by the tension adjusting rollers RT1 and RT2 by applying a predetermined tension to the substrate P in the longitudinal direction. However, the substrate P may slip with respect to the rotary drum DR due to the reason that the rotation speed Vp of the rotary drum DR is high, or the tension applied to the substrate P by the tension adjusting rollers RT1 and RT2 is too low or too high. When the count value by the encoders EN4a, 4b is the same as the count value (for example, 150) by the encoders EN1a, EN1b at the moment when the alignment microscope AM1m captures an image of the alignment mark MKmA (a specific alignment mark MKm) in a state where the substrate P does not slide with respect to the rotary drum DR, the alignment mark MKmA is detected by the alignment microscope AM2 m.

However, when the substrate P slips with respect to the rotary drum DR, even if the count value by the encoders EN4a, EN4b is the same as the count value (for example, 150) by the encoders EN1a, EN1b at the moment when the alignment microscope AM1m captures the alignment mark MKmA, the alignment mark MKmA is not detected by the alignment microscope AM2 m. In this case, for example, after the count value of the encoders EN4a and EN4b exceeds 150, the alignment mark MKmA is detected by the alignment microscope AM2 m. Therefore, the amount of slide with respect to the substrate P can be determined from the count values of the encoders EN1a and EN1b at the moment when the alignment mark MKmA is imaged by the alignment microscope AM1m and the count values of the encoders EN4a and EN4b at the moment when the alignment mark MKmA is imaged by the alignment microscope AM2 m. Thus, by additionally providing the alignment microscope AM2m and the encoders EN4a and EN4b, the amount of slide of the substrate P can be measured.

Next, an optical configuration of the scanning unit Un (U1 to U6) will be described with reference to fig. 5. Since each of the scan cells Un (U1 to U6) has the same configuration, only the scan cell (drawing cell) U1 will be described, and the description of the other scan cells Un will be omitted. In fig. 5, a direction parallel to the irradiation center axis Len (Le1) is referred to as a Zt direction, a direction on a plane orthogonal to the Zt direction and in which the substrate P passes from the processing apparatus PR2 to the processing apparatus PR3 through the exposure apparatus EX is referred to as an Xt direction, and a direction on a plane orthogonal to the Zt direction and orthogonal to the Xt direction is referred to as a Yt direction. That is, the three-dimensional coordinates of Xt, Yt, and Zt in fig. 5 are three-dimensional coordinates obtained by rotating the three-dimensional coordinate of X, Y, Z in fig. 2 around the Y axis so that the Z axis direction becomes parallel to the irradiation center axis Len (Le 1).

As shown in fig. 5, in the scanning unit U1, a mirror M10, a beam expander BE, a mirror M11, a polarization beam splitter BS1, a mirror M12, a shift optical member (transparent parallel plate) SR, a deflection adjusting optical member (prism) DP, a field stop FA, a mirror M13, a λ/4 wave plate QW, a cylindrical lens CYa, a mirror M14, a polygon mirror PM, an f θ lens FT, a mirror M15, and a cylindrical lens CYb are provided along the traveling direction of the light beam LB1 from the incident position of the light beam LB1 to the surface to BE irradiated (substrate P). Further, inside the scanning unit U1, an origin sensor (origin detector) OP1 for detecting a timing at which the scanning unit U1 can start drawing, an optical lens system G10 for detecting reflected light from the irradiated surface (substrate P) via the polarization beam splitter BS1, and a photodetector DT are provided.

The light beam LB1 incident on the scanning unit U1 is directed toward the-Zt direction, and is incident on the mirror M10 inclined at 45 ° to the XtYt plane. The beam LB1 incident on the scanning unit U1 is incident on the mirror M10 such that the axis thereof is coaxial with the irradiation center axis Le 1. The mirror M10 functions as an incident optical member for causing the light beam LB1 to enter the scanning unit U1, and reflects the incident light beam LB1 in the-Xt direction toward the mirror M11, which is separated from the mirror M10 in the-Xt direction, along the optical axis AXa set parallel to the Xt axis. Therefore, the optical axis AXa is orthogonal to the irradiation center axis Le1 in a plane parallel to the XtZt plane. The light beam LB1 reflected by the mirror M10 is transmitted through a beam expander BE disposed along the optical axis AXa and reflected to the mirror M11. The beam expander BE expands the diameter of the transmitted light beam LB 1. The beam expander BE includes a condenser lens BE1 and a collimator lens BE2 for making a beam LB1 converged by the condenser lens BE1 and then diverged into parallel light.

The mirror M11 is disposed to be inclined at 45 ° with respect to the YtZt plane, and reflects the incident light beam LB1 (optical axis AXa) in the-Yt direction toward the polarization beam splitter BS 1. The polarization splitting surface of the polarization beam splitter BS1 disposed apart from the mirror M11 in the-Yt direction is disposed inclined at 45 ° to the YtZt plane, and reflects the beam of P-polarized light and transmits the beam of linearly polarized light (S-polarized light) polarized in the direction orthogonal to the P-polarized light. Since the light beam LB1 incident on the scanning unit U1 is a beam of P-polarized light, the polarization beam splitter BS1 reflects the light beam LB1 from the reflecting mirror M11 toward the-Xt direction and guides it toward the reflecting mirror M12 side.

The mirror M12 is disposed to be inclined at 45 ° with respect to the XtYt plane, and reflects the incident beam LB1 in the-Zt direction toward the mirror M13 separated from the mirror M12 in the-Zt direction. The light beam LB1 reflected by the mirror M12 is incident on the mirror M13 along the optical axis AXc parallel to the Zt axis through the shift optical member SR, the deflection adjusting optical member DP, and the field stop FA. The shift optical member SR two-dimensionally adjusts the center position within the cross section of the light beam LB1 in a plane (XtYt plane) orthogonal to the traveling direction (optical axis AXc) of the light beam LB 1. The shift optical member SR is composed of parallel flat plates SR1, SR2 of 2 pieces of quartz arranged along the optical axis AXc, the parallel flat plate SR1 is tiltable around the Xt axis, and the parallel flat plate SR2 is tiltable around the Yt axis. The parallel flat plates Sr1, Sr2 are tilted about the Xt axis and the Yt axis, respectively, so that the position of the center of the beam LB1 is two-dimensionally shifted by a small amount in the XtYt plane orthogonal to the traveling direction of the beam LB 1. The parallel flat plates Sr1, Sr2 are driven by an actuator (driving unit), not shown, under the control of the controller 16. The parallel flat plate SR2 in the shift optical member SR functions as a mechanical-optical beam position adjustment member (the 1 st adjustment member, the 1 st adjustment optical member) that shifts the spot SP of the beam LB1 projected onto the substrate P in the sub-scanning direction (X direction in fig. 4) in a range of, for example, the size Φ of the spot SP or several to ten times the pixel size.

The deflection adjusting optical member DP finely adjusts the inclination of the light beam LB1 passing through the shift optical member SR after being reflected by the mirror M12 with respect to the optical axis AXc. The deflection adjusting optical member DP is configured by 2 wedge-shaped prisms DP1 and DP2 arranged along the optical axis AXc, and each of the prisms DP1 and DP2 is provided to be rotatable by 360 ° around the optical axis AXc independently. By adjusting the rotation angle positions of the 2 prisms Dp1, Dp2, the leveling between the axis of the light beam LB1 reaching the mirror M13 and the optical axis AXc, or the leveling between the axis of the light beam LB1 reaching the irradiated surface of the substrate P and the irradiation center axis Le1 is performed. Further, the light beam LB1 deflected and adjusted by the 2 prisms Dp1, Dp2 has a lateral shift in a plane parallel to the cross section of the light beam LB1, which can be restored to the original state by the above shift optical means SR. The prisms Dp1 and Dp2 are driven by an actuator (driving unit), not shown, under the control of the control device 16.

Thus, the light beam LB1 passing through the shift optical member SR and the deflection adjusting optical member DP passes through the circular opening of the field stop FA and reaches the mirror M13. The circular aperture of the field diaphragm FA is a diaphragm that cuts off (shields) the peripheral portion (base portion) of the intensity distribution in the cross section of the light beam LB1 expanded by the beam expander BE. The intensity (brightness) of the spot SP can be adjusted by setting the circular opening of the field diaphragm FA to a variable iris diaphragm with an adjustable aperture.

The mirror M13 is disposed to be inclined at 45 ° with respect to the XtYt plane, and reflects the incident light beam LB1 in the + Xt direction toward the mirror M14. The beam LB1 reflected by the mirror M13 is incident on the mirror M14 through the λ/4 plate QW and the cylindrical lens CYa. The mirror M14 reflects the incident light beam LB1 toward a polygon mirror (rotating polygon mirror, deflecting member for scanning) PM. The polygon mirror PM reflects the incident light beam LB1 toward the + Xt direction side toward an f θ lens FT having an optical axis AXf parallel to the Xt axis. The polygon mirror PM deflects (reflects) the incident light beam LB1 one-dimensionally in a plane parallel to the XtYt plane in order to scan the spot SP of the light beam LB1 on the surface of the substrate P to be irradiated. Specifically, the polygon mirror PM has a rotation axis AXp extending in the Zt-axis direction, and a plurality of reflection surfaces RP formed around the rotation axis AXp (in the present embodiment, the number Np of reflection surfaces RP is set to 8). The reflection angle of the pulse-shaped luminous flux LB1 irradiated on the reflection surface RP can be continuously changed by rotating the polygon mirror PM in a specific rotation direction about the rotation axis AXp. Thus, the light spot SP of the light beam LB1 irradiated on the irradiated surface of the substrate P can be scanned in the main scanning direction (the width direction of the substrate P, the Yt direction) by deflecting the reflection direction of the light beam LB1 by 1 reflection surface RP.

That is, the spot SP of the light beam LB1 can be scanned along the main scanning direction by 1 reflection surface RP. Therefore, the maximum number of the scanning lines SL1 on which the light spot SP scans the surface of the substrate P to be irradiated by 1 rotation of the polygon mirror PM is 8, which is the same as the number of the reflection surfaces RP. The polygon mirror PM is rotated at a fixed speed by a rotation drive source (e.g., a motor, a reduction mechanism, or the like) RM under the control of the control device 16. As described above, the effective length (for example, 30mm) of the drawing line SL1 is set to a length equal to or less than the maximum scanning length (for example, 31mm) over which the spot SP can be scanned by the polygon mirror PM, and the center point (point at which the irradiation center axis Le1 passes) of the drawing line SL1 is set at the center of the maximum scanning length at the time of initial setting (in design).

The cylindrical lens CYa converges the incident light beam LB1 on the reflection surface RP of the polygon mirror PM in the non-scanning direction (Zt direction) orthogonal to the main scanning direction (rotation direction) of the polygon mirror PM. That is, the cylindrical lens CYa has an elongated shape (oblong shape) that converges the light beam LB1 on the reflection surface RP so as to extend in a direction parallel to the XtYt plane. By the cylindrical lens CYa whose generatrix is parallel to the Yt direction and the cylindrical lens CYb described below, even when the reflection surface RP is inclined with respect to the Zt direction (inclination of the reflection surface RP with respect to the normal line of the XtYt plane), the influence thereof can be suppressed. That is, even if each reflection surface RP of the polygon mirror PM is slightly inclined from a state parallel to the rotation axis AXp, the irradiation position of the light beam LB1 (the drawing line SL1) irradiated onto the irradiated surface of the substrate P can be suppressed from being shifted in the Xt direction.

An f θ lens (scanning lens system) FT having an optical axis AXf extending in the Xt-axis direction is a telecentric scanning lens that projects the light beam LB1 reflected by the polygon mirror PM onto the mirror M15 so as to be parallel to the optical axis AXf in the XtYt plane. The incident angle θ of the light beam LB1 toward the f θ lens FT changes according to the rotation angle (θ/2) of the polygon mirror PM. The f θ lens FT projects the light beam LB1 to an image height position on the irradiated surface of the substrate P proportional to the incident angle θ via the mirror M15 and the cylindrical lens CYb. When the focal length is fo and the image height position is y, the f θ lens FT is designed to satisfy the relationship (distortion aberration) of y ═ fo × θ. Therefore, the f θ lens FT can accurately scan the light beam LB1 at a constant speed in the Yt direction (Y direction). When an incident angle θ of light beam LB1 on f θ lens FT is 0 degree, light beam LB1 incident on f θ lens FT travels along optical axis AXf.

The mirror M15 reflects the beam LB1 from the f θ lens FT toward the substrate P in the-Zt direction by passing through the cylindrical lens CYb. The light beam LB1 projected onto the substrate P is converged into a minute spot SP having a diameter of about several μm (for example, 3 μm) on the surface to be irradiated of the substrate P by the f θ lens FT and the cylindrical lens CYb having a bus line parallel to the Yt direction. The spot SP projected onto the irradiated surface of the substrate P is one-dimensionally scanned by the polygon mirror PM on the basis of the drawing line SL1 extending in the Yt direction. The optical axis AXf of the f θ lens FT is on the same plane as the irradiation center axis Le1, and the plane is parallel to the XtZt plane. Therefore, the light beam LB1 traveling on the optical axis AXf is reflected in the-Zt direction by the mirror M15, and is projected onto the substrate P coaxially with the irradiation center axis Le 1. In embodiment 1, at least the f θ lens FT functions as a projection optical system that projects the light beam LB1 deflected by the polygon mirror PM onto the surface of the substrate P to be irradiated. At least the reflecting members (the reflecting mirrors M11 to M15) and the polarization beam splitter BS1 function as optical path deflecting members for bending the optical path of the light beam LB1 from the reflecting mirror M10 to the substrate P. The incident axis of the light beam LB1 incident on the mirror M10 and the irradiation center axis Le1 can be made substantially coaxial by the optical path deflecting member. In the XtZt plane, the light beam LB1 passing through the scanning unit U1 passes through a substantially U-shaped or コ -shaped optical path, and then advances in the-Zt direction to be projected onto the substrate P.

By one-dimensionally scanning the spot SP of the light beam LBn (LB1 to LB6) in the main scanning direction (Y direction) by the scanning units Un (U1 to U6) in the state where the substrate P is transported in the X direction in this manner, the spot SP can be relatively two-dimensionally scanned on the irradiation surface of the substrate P.

As an example, when the effective length of the scanning line SLn (SL1 to SL6) is set to 30mm and the light spot SP is irradiated onto the irradiation surface of the substrate P along the scanning line SLn (SL1 to SL6) every time the light spot SP is irradiated with 1/2, i.e., 1.5 μm overlapped with 1.5 μm of the pulse-shaped light spot SP having an effective size Φ of 3 μm. Therefore, the number of pulses of the spot SP irradiated by 1 scan is 20000(═ 30 [ mm ]/1.5 [ μm ]). When scanning of the spot SP is performed at intervals of 1.5 μm in the sub-scanning direction, the conveyance speed (conveyance speed) Vt [ mm/sec ] in the sub-scanning direction of the substrate P becomes 1.5 [ μm ]/Tpx [ μ sec ] when the time difference between the scanning start (drawing start) time point and the next scanning start time point of 1 time along the scanning line SLn is Tpx [ μ sec ]. The time difference Tpx is a time when the polygon mirror PM of the 8 reflection surface RP rotates by 1 plane (45 degrees 360 degrees/8). In this case, the time required for 1 rotation of the polygon mirror PM must be set to 8 × Tpx [ μ sec ].

On the other hand, the maximum incident angle (corresponding to the maximum scanning length of the spot SP) at which the light beam LB1 reflected by the 1 reflection surface RP of the polygon mirror PM is efficiently incident on the f θ lens FT is approximately determined by the focal length and the maximum scanning length of the f θ lens FT and the thickness (numerical aperture: NA) in the main scanning direction of the light beam LB1 incident on the 1 reflection surface RP of the polygon mirror PM. For example, in the case of the polygon mirror PM of the 8 reflection surface RP, the ratio of the rotation angle α contributing to actual scanning (scanning efficiency) out of the rotation angles of 45 degrees corresponding to the 1 reflection surface RP is represented by α/45 degrees. In embodiment 1, since the rotation angle α contributing to actual scanning is set to 15 degrees, the scanning efficiency is 1/3 (15 degrees/45 degrees), and the maximum incident angle of the f θ lens FT is 30 degrees (± 15 degrees around the optical axis AXf). Therefore, the time Ts [ μ sec ] required for scanning the spot SP with the maximum scanning length (for example, 31mm) of the drawing line SLn is set to Tpx × scanning efficiency. Since the effective scanning length of the drawing line SLn (SL1 to SL6) in embodiment 1 is 30mm, the scanning time Tsp [ μ sec ] of 1 scan of the spot SP along the drawing line SLn becomes Tsp × 30 [ mm ]/31 [ mm ]. Therefore, 20000 spots SP (pulsed light) must be irradiated during the time Tsp, and thus the emission frequency (oscillation frequency) Fa of the light beam LB from the light source device LS (LSa, LSb) is equal to Fa ≈ 20000/Tsp [ μ sec ].

The origin sensor OP1 shown in fig. 5 generates the origin signal SZ1 when the rotational position of the reflection surface RP of the polygon mirror PM reaches a specific position where scanning of the light spot SP by the reflection surface RP can be started. In other words, the origin sensor OP1 generates the origin signal SZ1 when the angle of the reflection surface RP which scans the spot SP next becomes a specific angular position. Since the polygon mirror PM has 8 reflection surfaces RP, the origin sensor OP1 outputs the origin signal SZ 18 times during 1 rotation of the polygon mirror PM. The origin sensor OP1 generates an origin signal SZ1, which is sent to the control device 16. After a delay time Td1 elapses after the origin sensor OP1 generates the origin signal SZ1, scanning of the spot SP along the scanning line SL1 is started. That is, the origin signal SZ1 is information indicating the drawing start timing (scanning start timing) of the spot SP by the scanning unit U1.

The origin sensor OP1 includes: a beam delivery system opa for emitting a laser beam Bga in a wavelength region that is not photosensitive with respect to the photosensitive functional layer of the substrate P to the reflection surface RP; and a beam photo-detector opb that receives the reflected beam Bgb of the laser beam Bga reflected by the reflection surface RP and generates an origin signal SZ 1. Although not shown, the beam delivery system opa includes a light source that emits the laser beam Bga, and an optical member (such as a mirror or a lens) that projects the laser beam Bga emitted from the light source onto the reflection surface RP. Although not shown, the light beam receiving system opb includes: a light receiving portion including a photoelectric conversion element that receives the received reflected light beam Bgb and converts it into an electrical signal; and an optical member (such as a mirror or a lens) for guiding the reflected light beam Bgb reflected by the reflection surface RP to the light receiving section. The beam transmitting system opa and the beam receiving system opb are provided at positions where the beam receiving system opb can receive the reflected beam Bgb of the laser beam Bga emitted from the beam transmitting system opa when the rotational position of the polygon mirror PM reaches a specific position immediately before the scanning of the spot SP by the reflection surface RP. Origin sensors OPn provided in the scan cells U2 to U6 are denoted by OP2 to OP6, and origin signals SZn generated by the origin sensors OP2 to OP6 are denoted by SZ2 to SZ 6. The controller 16 manages which scanning unit Un scans the spot SP next based on the origin signal SZn (SZ1 to SZ 6). Further, delay times Tdn from the generation of the origin signals SZ2 to SZ6 to the start of scanning of the spot SP along the scanning lines SL2 to SL6 by the scanning units U2 to U6 may be represented by Td2 to Td 6.

The photodetector DT shown in fig. 5 has a photoelectric conversion element that photoelectrically converts incident light. A predetermined reference pattern is formed on the surface of the rotary drum DR. The portion of the rotary drum DR on which the reference pattern is formed is made of a material having a slightly lower reflectance (10 to 50%) with respect to the wavelength region of the light beam LB1, and the other portion of the rotary drum DR on which the reference pattern is not formed is made of a material having a reflectance of 10% or less or a material that absorbs light. Therefore, when the spot SP of the light beam LB1 is irradiated from the scanning unit U1 to the area where the reference pattern is formed of the rotary drum DR in a state where the substrate P is not wound (or in a state where the light beam passes through the transparent portion of the substrate P), the reflected light passes through the cylindrical lens CYb, the mirror M15, the f θ lens FT, the polygon mirror PM, the mirror M14, the cylindrical lens CYa, the λ/4 wave plate QW, the mirror M13, the field stop FA, the deflection adjusting optical member DP, the shifting optical member SR, and the mirror M12 and enters the polarization beam splitter BS 1. Here, a λ/4 wave plate QW is provided between the polarization beam splitter BS1 and the substrate P, specifically, between the mirror M13 and the cylindrical lens CYa. Thus, the light beam LB1 irradiated on the substrate P is the light beam LB1 converted from P-polarized light to circularly polarized light by the λ/4 plate QW, and the reflected light incident on the polarization beam splitter BS1 from the substrate P is converted from circularly polarized light to S-polarized light by the λ/4 plate QW. Therefore, the reflected light from the substrate P is transmitted through the polarization beam splitter BS1 and enters the photodetector DT through the optical lens system G10.

At this time, the light spot SP is two-dimensionally irradiated on the outer peripheral surface of the rotary drum DR by rotating the rotary drum DR and scanning the light spot SP by the scanning unit U1 in a state where the pulsed light beam LB1 is continuously incident on the scanning unit U1. Therefore, an image signal (photoelectric signal corresponding to the reflection intensity) of the reference pattern formed on the rotating drum DR can be acquired by the photodetector DT.

Specifically, the intensity change of the photoelectric signal output from the photodetector DT is acquired as one-dimensional image data in the Yt direction by digitally sampling the signal LTC (generated by the light source device LS) in response to the pulse light emission for the light beam LB1 (light spot SP). Further, in response to the measurement values of the encoders EN2a, EN2b that measure the rotational angle position of the rotary drum DR on the scanning line SL1, the one-dimensional image data in the Yt direction is aligned in the Xt direction at regular intervals in the sub-scanning direction (for example, 1/2 of the size Φ of the spot SP), whereby two-dimensional image information of the surface of the rotary drum DR can be acquired. The controller 16 measures the inclination of the drawing line SL1 of the scanner unit U1 based on the acquired two-dimensional image information of the reference pattern of the rotary drum DR. The inclination of the drawing line SL1 may be relative inclination between the scanning units Un (U1 to U6) or inclination (absolute inclination) with respect to the central axis AXo of the rotary drum DR. Needless to say, the inclination of each of the drawing lines SL2 to SL6 may be measured in the same manner. Further, by analyzing the two-dimensional image information of the reference pattern obtained by the photodetector DT, in addition to the tilt error of each of the drawing lines SL2 to SL6, the position error of the drawing start point or the drawing end point of each of the drawing lines SL2 to SL6, the joint error of each of the drawing lines SL2 to SL6, and the like can be confirmed, and the calibration of each of the scanning units Un (U1 to U6) can be realized.

The plurality of scanning units Un (U1 to U6) are held by a main body frame (not shown) so that each of the plurality of scanning units Un (U1 to U6) can rotate (revolve) around an irradiation center axis Len (Le1 to Le 6). When the scanning units Un (U1 to U6) rotate around the irradiation center axes Len (Le1 to Le6), the scanning lines SLn (SL1 to SL6) also rotate around the irradiation center axes Len (Le1 to Le6) on the irradiated surface of the substrate P. Therefore, the drawing lines SLn (SL1 to SL6) are inclined with respect to the Y direction. That is, when the scanning units Un (U1 to U6) are rotated around the irradiation center axes Len (Le1 to Le6), the relative positional relationship between the light beams LBn (LB1 to LB6) passing through the scanning units Un (U1 to U6) and the optical members in the scanning units Un (U1 to U6) is not changed. Therefore, each of the scanning units Un (U1 to U6) can scan the spot SP on the irradiated surface of the substrate P along the rotated drawing lines SLn (SL1 to SL 6). The rotation of the scanning units Un (U1 to U6) around the irradiation center axes Len (Le1 to Le6) is performed by an actuator (not shown) under the control of the controller 16.

Therefore, the controller 16 can maintain the parallel state of the plurality of scanning lines SLn (SL1 to SL6) by rotating the scanning unit Un (U1 to U6) around the irradiation center axis Len (Le1 to Le6) in accordance with the measured inclination of each scanning line SLn. When the substrate P or the exposed region W is strained (deformed) according to the position of the alignment mark MKm detected by the alignment microscopes AM1m and AM2m, the pattern to be drawn must be strained accordingly. Therefore, when the controller 16 determines that the substrate P or the exposure area W is strained (deformed), the scanning unit Un (U1 to U6) is rotated around the irradiation center axis Len (Le1 to Le6), and the drawing lines SLn are slightly inclined with respect to the Y direction in accordance with the strain (deformation) of the substrate P or the exposure area W. In this case, as described below, the present embodiment can perform control such that the pattern drawn along each of the drawing lines SLn is expanded and contracted according to a specified magnification (for example, ppm level), or control such that each of the drawing lines SLn is slightly shifted in the sub-scanning direction (Xt direction in fig. 5) individually.

Even if the irradiation center axis Len of the scanning unit Un does not completely coincide with the axis (rotation center axis) about which the scanning unit Un actually rotates, the two may be coaxial within a specific allowable range. The specific allowable range is set such that a difference between the actual drawing start point (or drawing end point) of the drawing line SLn when the scanning unit Un is rotated at the angle θ sm and the design drawing start point (or drawing end point) of the drawing line SLn when the scanning unit Un is rotated at the specific angle θ sm when the irradiation center axis Len and the rotation center axis are assumed to completely coincide is within a specific distance (for example, the size Φ of the spot SP) in the main scanning direction of the spot SP. Even if the optical axis of the light flux LBn actually incident on the scanning unit Un does not completely coincide with the rotation center axis of the scanning unit Un, the light flux LBn may be coaxial within the above-described specific allowable range.

Fig. 6 is a configuration diagram of the beam switching unit BDU. The beam switching unit BDU includes a plurality of selection optical elements AOMn (AOM1 to AOM6), a plurality of condenser lenses CD1 to CD6, a plurality of reflection mirrors M1 to M14, a plurality of cell-side incident mirrors IM1 to IM6(IMn), a plurality of collimator lenses CL1 to CL6, and absorbers TR1 and TR 2. The optical selection elements AOMn (AOM 1-AOM 6) are transmissive to the light beam LB (LBa, LBb), and are Acousto-Optic modulators (AOM) driven by ultrasonic signals. These optical members (selective optical elements AOM1 to AOM6, condenser lenses CD1 to CD6, mirrors M1 to M14, cell-side incident mirrors IM1 to IM6, collimator lenses CL1 to CL6, and absorbers TR1, TR2) are supported by a plate-shaped support member IUB. The support member IUB supports the optical members from above (+ Z direction side) of the plurality of scanning units Un (U1-U6) from below (-Z direction side). Therefore, the support member IUB also has a function of thermally insulating the optical element AOMn (AOM1 to AOM6) for selection serving as a heat generation source from the plurality of scanning units Un (U1 to U6).

The light beam LBa from the light source device LSa is guided to the absorber TR1 by bending its optical path into a zigzag shape by the mirrors M1-M6. Similarly, the light beam LBb from the light source device LSb is guided to the absorber TR2 by bending the optical path thereof into a zigzag shape by the mirrors M7 to M14. Hereinafter, the selective optical elements AOMn (AOM1 to AOM6) are all in an off state (a state where no ultrasonic signal is applied) and will be described in detail.

A light beam LBa (for example, a parallel light beam having a diameter of 1mm or less) from the light source device LSa advances in the + Y direction in parallel with the Y axis, passes through the condenser lens CD1, and enters the mirror M1. The light beam LBa reflected in the-X direction by the mirror M1 passes through the 1 st selective optical element AOM1 disposed at the focal position (beam waist position) of the condenser lens CD1, becomes a parallel light beam again by the collimator lens CL1, and reaches the mirror M2. The light beam LBa reflected in the + Y direction by the mirror M2 passes through the condenser lens CD2 and is then reflected in the + X direction by the mirror M3.

The light beam LBa reflected in the + X direction by the mirror M3 passes through the 2 nd selective optical element AOM2 disposed at the focal position (beam waist position) of the condenser lens CD2, becomes a parallel light beam again by the collimator lens CL2, and reaches the mirror M4. The light beam LBa reflected by the mirror M4 in the + Y direction is reflected by the mirror M5 in the-X direction after passing through the condenser lens CD 3. The light flux LBa reflected in the-X direction by the mirror M5 passes through the 3 rd selective optical element AOM3 disposed at the focal position (beam waist position) of the condenser lens CD3, becomes a parallel light flux again by the collimator lens CL3, and reaches the mirror M6. The light beam LBa reflected in the + Y direction by the mirror M6 is incident on the absorber TR 1. The absorber TR1 is a light collector that absorbs the light beam LBa in order to suppress leakage of the light beam LBa to the outside.

A light beam LBb (e.g., a parallel light beam having a diameter of 1mm or less) from the light source device LSb advances in the + Y direction in parallel with the Y axis and enters the mirror M13, and the light beam LBb reflected in the + X direction by the mirror M13 is reflected in the + Y direction by the mirror M14. The light beam LBb reflected by the mirror M14 in the + Y direction is reflected by the mirror M7 in the + X direction after passing through the condenser lens CD 4. The light beam LBb reflected in the + X direction by the mirror M7 passes through the 4 th selective optical element AOM4 disposed at the focal position (beam waist position) of the condenser lens CD4, becomes a parallel light beam again by the collimator lens CL4, and reaches the mirror M8. The light beam LBb reflected by the mirror M8 in the + Y direction is reflected by the mirror M9 in the-X direction after passing through the condenser lens CD 5.

The light beam LBb reflected in the-X direction by the mirror M9 passes through the 5 th selective optical element AOM5 disposed at the focal position (beam waist position) of the condenser lens CD5, becomes a parallel beam again by the collimator lens CL5, and reaches the mirror M10. The light beam LBb reflected by the mirror M10 in the + Y direction is reflected by the mirror M11 in the + X direction after passing through the condenser lens CD 6. The light flux LBb reflected in the + X direction by the mirror M11 passes through the 6 th selective optical element AOM6 disposed at the focal position (beam waist position) of the condenser lens CD6, becomes a parallel light flux again by the collimator lens CL6, and reaches the mirror M12. The light beam LBb reflected in the-Y direction by the mirror M12 is incident on the absorber TR 2. The absorber TR2 is a light collector that absorbs the light beam LBb in order to suppress the light beam LBb from leaking to the outside.

As described above, the optical elements AOM1 to AOM3 are arranged in series along the traveling direction of the light beam LBa so that the light beam LBa from the light source device LSa sequentially transmits therethrough. The optical elements AOM1 to AOM3 are arranged so that the beam waist of the beam LBa is formed inside the optical elements AOM1 to AOM3 by the condenser lenses CD1 to CD3 and the collimator lenses CL1 to CL 3. Thereby, the diameters of the light fluxes LBa incident on the selective optical elements (acousto-optic modulators) AOM1 to AOM3 are reduced to improve diffraction efficiency and improve responsiveness. Similarly, the optical elements AOM4 to AOM6 are arranged in series along the traveling direction of the light beam LBb so that the light beam LBb from the light source device LSb sequentially transmits. The optical elements AOM4 to AOM6 are arranged so that the beam waist of the beam LBb is formed inside the optical elements AOM4 to AOM6 by the condenser lenses CD4 to CD6 and the collimator lenses CL4 to CL 6. This reduces the diameter of the light beam LBb incident on the selective optical elements (acousto-optic modulators) AOM4 to AOM6, thereby improving diffraction efficiency and responsiveness.

When an ultrasonic signal (high-frequency signal) is applied to each of the selective optical elements AOMn (AOM1 to AOM6), 1-order diffracted light is generated as an outgoing light beam (light beam LBn), the 1-order diffracted light being obtained by diffracting the incident light beam (0-order light) LB (LBa, LBb) at a diffraction angle corresponding to a frequency of a high frequency. In embodiment 1, the light beam LBn emitted as 1-time diffracted light from each of the plurality of selective optical elements AOMn (AOM1 to AOM6) is referred to as light beams LB1 to LB6, and the respective selective optical elements AOMn (AOM1 to AOM6) are handled as a function of deflecting the optical paths of the light beams LB (LBa, LBb) from the light source apparatuses LSa, LSb. However, in the actual acousto-optic modulator, since the generation efficiency of the 1 st-order diffracted light is about 80% of that of the 0 th-order light, the intensity of the light beam LBn (LB1 to LB6) after being deflected by each of the selection optical elements AOMn (AOM1 to AOM6) is lower than that of the original light beam LB (LBa, LBb). When any of the selective optical elements AOMn (AOM1 to AOM6) is in an on state, about 20% of 0-time light remains that advances linearly without being diffracted, but is finally absorbed by the absorbers TR1 and TR 2.

As shown in fig. 6, each of the plurality of optical elements for selection AOMn (AOM1 to AOM6) is provided so as to deflect the light flux LBn (LB1 to LB6) which is the deflected 1-time diffracted light in the-Z direction with respect to the incident light flux LB (LBa, LBb). The light fluxes LBn (LB1 to LB6) deflected and emitted from the respective optical elements for selection AOMn (AOM1 to AOM6) are projected onto the cell-side incidence mirrors IM1 to IM6 provided at positions distant from the respective optical elements for selection AOMn (AOM1 to AOM6) by a predetermined distance, and then reflected coaxially with the irradiation central axes Le1 to Le6 in the-Z direction. The light beams LB1 to LB6 reflected by the cell-side incident mirrors IM1 to IM6 (hereinafter, also simply referred to as mirrors IM1 to IM6) pass through the openings TH1 to TH6 formed in the support member IUB and are incident on the respective scanning cells Un (U1 to U6) along the irradiation center axes Le1 to Le 6.

Further, since the optical element AOMn is a diffraction grating that generates a periodic density change of a refractive index in a specific direction in the transmission member by an ultrasonic wave, when the incident light beam LB (LBa, LBb) is linearly polarized light (P-polarized light or S-polarized light), the polarization direction and the periodic direction of the diffraction grating are set so that the generation efficiency (diffraction efficiency) of 1-time diffracted light becomes the highest. As shown in fig. 6, when each of the selective optical elements AOMn is provided so as to diffract and deflect the incident light beam LB (LBa, LBs) in the-Z direction, the polarization direction of the light beam LB from the light source device LS (LSa, LSb) is set (adjusted) so as to match the periodic direction of the diffraction grating generated in the selective optical element AOMn also in the-Z direction.

The optical elements AOMn for selection (AOM 1-AOM 6) may be used in the same structure, function and action. The plurality of optical elements for selection AOMn (AOM1 to AOM6) perform/do not perform generation of diffracted light obtained by diffracting the incident light beams LB (LBa, LBb) in accordance with on/off of a drive signal (high frequency signal) from the control device 16. For example, the selective optical element AOM1 transmits the incident light beam LBa from the light source device LSa without being diffracted when the optical element is in the off state without being applied with the drive signal (high frequency signal) from the control device 16. Therefore, the light beam LBa having passed through the optical element AOM1 for selection passes through the collimator lens CL1 and enters the mirror M2. On the other hand, the optical element AOM1 diffracts the incident light beam LBa to direct it toward the mirror IM1 when the optical element is turned on by the application of a drive signal (high-frequency signal) from the control device 16. That is, the optical selection element AOM1 is switched according to the drive signal. The mirror IM1 selects the beam LB1, which is the 1 st diffracted light diffracted by the selective optical element AOM1, and reflects the beam LB toward the scanning unit U1. The light beam LB1 reflected by the selective mirror IM1 enters the scanning unit U1 along the irradiation center axis Le1 through the opening TH1 of the support member IUB. Therefore, the mirror IM1 reflects the incident beam LB1 so that the optical axis of the reflected beam LB1 is coaxial with the irradiation center axis Le 1. When the selective optical element AOM1 is in the on state, 0 th light (intensity of about 20% of incident light flux) of the light beam LB that has directly transmitted through the selective optical element AOM1 reaches the absorber TR1 through the collimator lenses CL1 to CL3, the condenser lenses CD2 to CD3, the mirrors M2 to M6, and the selective optical elements AOM2 to AOM3 after transmission.

Similarly, the optical elements AOM2 and AOM3 transmit the incident light beam LBa (0 th order light) toward the collimator lenses CL2 and CL3 (toward the mirrors M4 and M6) without diffracting the light beam LBa when the optical elements are in the off state without applying a drive signal (high frequency signal) from the control device 16. On the other hand, when the selection optical elements AOM2 and AOM3 are turned on by the drive signal from the control device 16, the light fluxes LB2 and LB3, which are the 1 st-order diffracted lights of the incident light flux LBa, are directed toward the mirrors IM2 and IM 3. The mirrors IM2, IM3 reflect the beams LB2, LB3 diffracted by the selective optical elements AOM2, AOM3 toward the scanning units U2, U3. The light beams LB2 and LB3 reflected by the mirrors IM2 and IM3 enter the scanning units U2 and U3 through the openings TH2 and TH3 of the support member IUB coaxially with the irradiation central axes Le2 and Le 3.

In this manner, the control device 16 switches any one of the selective optical elements AOM1 to AOM3 by turning on/off (high/low) the drive signal (high frequency signal) applied to each of the selective optical elements AOM1 to AOM3, and switches the direction of the light beam LBa toward the scanning units U1 to U3 corresponding to the following selective optical element AOM2, AOM3, or absorber TR1, or 1 of the deflected light beams LB1 to LB 3.

When the selection optical element AOM4 is in the off state without the application of the drive signal (high-frequency signal) from the control device 16, the incident light beam LBb from the light source device LSb is transmitted toward the collimator lens CL4 (toward the mirror M8) without being diffracted. On the other hand, when the selection optical element AOM4 is turned on by the application of the drive signal from the control device 16, the light beam LB4, which is the 1 st-order diffracted light of the incident light beam LBb, is directed toward the mirror IM 4. The mirror IM4 reflects the light beam LB4 diffracted by the selective optical element AOM4 toward the scanning unit U4. The light beam LB4 reflected by the mirror IM4 passes through the opening TH4 of the support member IUB coaxially with the irradiation center axis Le4 and enters the scanning unit U4.

Similarly, the optical elements AOM5 and AOM6 transmit the incident light beam LBb to the collimator lenses CL5 and CL6 (mirrors M10 and M12) without diffracting the incident light beam LBb when the elements are in the off state without applying a drive signal (high frequency signal) from the control device 16. On the other hand, when the selection optical elements AOM5 and AOM6 are turned on by the drive signal from the control device 16, the light fluxes LB5 and LB6, which are the 1 st-order diffracted lights of the incident light flux LBb, are directed toward the mirrors IM5 and IM 6. The mirrors IM5, IM6 reflect the beams LB5, LB6 diffracted by the selective optical elements AOM5, AOM6 toward the scanning units U5, U6. The light beams LB5 and LB6 reflected by the mirrors IM5 and IM6 pass through the openings TH5 and TH6 of the support member IUB coaxially with the irradiation center axes Le5 and Le6 and enter the scanning units U5 and U6, respectively.

In this manner, the control device 16 switches any one of the selective optical elements AOM4 to AOM6 by turning on/off (high/low) the drive signal (high frequency signal) applied to each of the selective optical elements AOM4 to AOM6, and switches the direction of the light beam LBb to the next selective optical element AOM5, AOM6, or absorber TR2, or 1 of the deflected light beams LB4 to LB6 to the corresponding scanning units U4 to U6.

As described above, the beam switching unit BDU includes the plurality of optical selection elements AOMn (AOM1 to AOM3) arranged in series along the traveling direction of the light beam LBa from the light source device LSa, and is capable of switching the optical path of the light beam LBa to select 1 scanning unit Un (U1 to U3) on which the light beam LBn (LB1 to LB3) enters. Therefore, the light beam LBn (LB1 to LB3), which is 1-time diffracted light of the light beam LBa from the light source device LSa, can be sequentially incident on each of the 3 scanning units Un (U1 to U3). For example, when the light beam LB1 is to be incident on the scanning unit U1, the control device 16 may set only the selective optical element AOM1 of the plurality of selective optical elements AOM1 to AOM3 to the on state, and when the light beam LB3 is to be incident on the scanning unit U3, only the selective optical element AOM3 may be set to the on state.

Similarly, the beam switching unit BDU includes a plurality of optical elements AOMn (AOM4 to AOM6) for selection arranged in series along the traveling direction of the light beam LBb from the light source device LSb, and is capable of switching the optical path of the light beam LBb to select 1 scanning unit Un (U4 to U6) on which the light beam LBn (LB4 to LB6) enters. Therefore, the light beam LBn (LB4 to LB6), which is 1-time diffracted light of the light beam LBb from the light source device LSb, can be sequentially incident on each of the 3 scanning units Un (U4 to U6). For example, when the light beam LB4 is to be incident on the scanning unit U4, the control device 16 may set only the selective optical element AOM4 of the plurality of selective optical elements AOM4 to AOM6 to the on state, and when the light beam LB6 is to be incident on the scanning unit U6, only the selective optical element AOM6 may be set to the on state.

The plurality of optical elements for selection AOMn (AOM1 to AOM6) are provided in correspondence with the plurality of scanning units Un (U1 to U6), and switch whether or not the light beam LBn is incident on the corresponding scanning unit Un. In embodiment 1, the optical elements for selection AOM1 to AOM3 are referred to as optical element module 1, and the optical elements for selection AOM4 to AOM6 are referred to as optical element module 2. The scanning units U1 to U3 corresponding to the optical elements AOM1 to AOM3 for selection of the 1 st optical element module are referred to as the 1 st scanning module, and the scanning units U4 to U6 corresponding to the optical elements AOM4 to AOM6 for selection of the 2 nd optical element module are referred to as the 2 nd scanning module. Therefore, the scanning of the spot SP is performed in parallel with any of the scanning units Un of the 1 st scanning module and any of the scanning units Un of the 2 nd scanning module.

As described above, in embodiment 1, since the rotation angle α of the polygon mirror PM of the scanning unit Un contributing to the actual scanning is set to 15 degrees, the scanning efficiency becomes 1/3. Therefore, for example, while 1 scanning unit Un is rotated by an angle (45 degrees) corresponding to 1 reflection surface RP, the angle at which scanning of spot SP is possible is 15 degrees, and in the other angular range (30 degrees), scanning of spot SP is not possible, and the light beam LBn incident on the polygon mirror PM is wasted. Therefore, while the rotation angle of the polygon mirror PM of one of the scanning units Un is at an angle that does not contribute to actual scanning, the light beam LBn can be made incident on the other scanning units Un, and the scanning of the spot SP can be performed by the polygon mirror PM of the other scanning units Un. Since the scanning efficiency of the polygon mirror PM is 1/3, the scanning of the spot SP can be performed by distributing the light beam LBn to the other 2 scanning units Un during the period from when one scanning unit Un scans the spot SP to before the next scanning is performed. Therefore, in embodiment 1, the plurality of scan cells Un (U1 to U6) are divided into 2 groups (scan modules), 3 scan cells U1 to U3 are referred to as the 1 st scan module, and 3 scan cells U4 to U6 are referred to as the 2 nd scan module.

Thus, for example, while the polygon mirror PM of the scanning unit U1 rotates by 45 degrees (corresponding to the 1 reflection surface RP), the light beam LBn (LB1 to LB3) can be sequentially incident on any of the 3 scanning units U1 to U3. Therefore, each of the scanning units U1 to U3 can sequentially scan the light spot SP with the light beam LBa from the light source device LSa without waste. Similarly, while the polygon mirror PM of the scanning unit U4 rotates by 45 degrees (corresponding to the 1 reflection surface RP), the light beam LBn (LB4 to LB6) can be sequentially incident on any of the 3 scanning units U4 to U6. Therefore, the scanning units U4 to U6 can sequentially scan the light spot SP with the light beam LBb from the light source device LSb without waste. Further, the polygon mirror PM rotates by an angle (45 degrees) corresponding to 1 reflection surface RP during a period from when each scanning unit Un starts scanning of the spot SP to before the next scanning starts.

In the embodiment 1, since each of the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module scans the light spot SP in a specific order, the control device 16 switches on the 3 selective optical elements AOMn (AOM1 to AOM3, AOM4 to AOM6) of each optical element module in a specific order and sequentially switches the scanning units Un (U1 to U3, U4 to U6) on which the light beams LBn (LB1 to LB3, LB4 to LB6) enter. For example, when the scanning order of the spot SP by the 3 scanning units U1 to U3 and U4 to U6 of each scanning module is U1 → U2 → U3 and U4 → U5 → U6, the control device 16 switches the 3 optical elements AOMn for selection (AOM1 to AOM3 and AOM4 to AOM6) of each optical element module to on in the order of AOM1 → AOM2 → AOM3 and AOM4 → AOM5 → AOM6, and switches the scanning unit Un into which the light beam LBn enters in the order of U1 → U2 → U3, U4 → U5 → U6.

In order to scan the spot SP sequentially by the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module while the polygon mirror PM rotates by an angle (45 degrees) corresponding to 1 reflection surface RP, the polygon mirror PM of the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module must rotate while satisfying the following condition. This condition means that the respective polygon mirrors PM of the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module must be synchronously controlled so as to have the same rotational speed Vp, and that the rotational angle positions of the respective polygon mirrors PM (the angular positions of the respective reflection surfaces RP) must be synchronously controlled so as to have a specific phase relationship. The rotation of the polygon mirror PM of the 3 scanning units Un of each scanning module at the same rotational speed Vp is referred to as synchronous rotation.

Fig. 7 is a diagram showing the structure of the light source device (pulse light source device, pulse laser device) lsa (lsb). The light source device lsa (lsb) as a fiber laser device includes a pulsed light generator 20 and a control circuit 22. The pulse light generating unit 20 includes DFB

semiconductor laser elements

30 and 32, a polarization beam splitter 34, a photoelectric element (intensity modulating unit) 36 as a drawing light modulator, a drive circuit 36a of the photoelectric element 36, a polarization beam splitter 38, an absorber 40, an excitation light source 42, a combiner 44, a fiber optical amplifier 46, wavelength conversion

optical elements

48 and 50, and a plurality of lens elements GL. The control circuit 22 includes a signal generating section 22a for generating a clock signal LTC and a pixel shift pulse BSC. In order to distinguish the pixel shift pulse BSC output from the signal generating section 22a of the light source device LSa from the pixel shift pulse BSC output from the signal generating section 22a of the light source device LSb, the pixel shift pulse BSC from the light source device LSa may be represented by BSCa, and the pixel shift pulse BSC from the light source device LSb may be represented by BSCb.

The DFB semiconductor laser device (1 st solid-state laser device) 30 generates a genuinely sharp or sharply pulsed seed light (pulse beam, beam) S1 at an oscillation frequency Fa (for example, 400MHz) that is a specific frequency, and the DFB semiconductor laser device (2 nd solid-state laser device) 32 generates a slowly (temporally wide) pulsed seed light (pulse beam, beam) S2 at an oscillation frequency Fa (for example, 400MHz) that is a specific frequency, in cooperation with a pulse wave extraction system such as a Q switch (not shown). The seed light S1 generated by the DFB semiconductor laser element 30 is synchronized with the seed light S2 generated by the DFB semiconductor laser element 32 in terms of emission timing. The seed lights S1 and S2 have approximately the same energy per 1 pulse, but have different polarization states, and the peak intensity is strong as the seed light S1. The seed light S1 and the seed light S2 are linearly polarized light, and the polarization directions thereof are orthogonal to each other. In embodiment 1, the polarization state of the seed light S1 generated by the DFB semiconductor laser device 30 is S-polarized light, and the polarization state of the seed light S2 generated by the DFB semiconductor laser device 32 is P-polarized light. The lights S1 and S2 are lights in the infrared wavelength range.

The control circuit 22 controls the DFB

semiconductor laser elements

30 and 32 so as to emit the seed lights S1 and S2 in response to the clock pulse of the clock signal LTC transmitted from the signal generating unit 22 a. Thus, the DFB

semiconductor laser elements

30 and 32 emit seed lights S1 and S2 at a specific frequency (oscillation frequency) Fa in response to each clock pulse (oscillation frequency Fa) of the clock signal LTC. The control circuit 22 is controlled by the control device 16. The period of the clock pulse of the clock signal LTC (═ 1/Fa) is referred to as a reference period Ta. The seed lights S1, S2 generated by the DFB

semiconductor laser elements

30, 32 are guided to the polarization beam splitter 34.

The clock signal LTC serving as a reference clock signal is a reference of the pixel shift pulses BSC (BSCa, BSCb) supplied to the counter units for specifying addresses in the row direction in the memory circuit of the dot matrix pattern data, and will be described in detail later. Further, the control device 16 inputs, to the signal generating unit 22a, total magnification correction information TMg for performing total magnification correction of the drawn line SLn on the irradiated surface of the substrate P, and local magnification correction information CMgn for performing local magnification correction of the drawn line SLn (CMg1 to CMg 6). Thus, the length of the pattern drawn by the drawing line SLn on the irradiated surface of the substrate P (pattern drawing length) can be finely adjusted, which will be described in detail below. The expansion and contraction of the pattern drawing length (fine adjustment of the scanning length) can be performed in a range of, for example, about ± 1000ppm within the maximum scanning length (for example, 31mm) of the drawing line SLn. In addition, in the overall magnification correction in embodiment 1, for simplicity of explanation, the projection interval of the light spot SP projected in the main scanning direction (that is, the oscillation frequency of the light spot) is uniformly fine-adjusted while the number of light spots included in 1 pixel (1 bit) on the drawing data is kept constant, and the drawing magnification in the scanning direction of the entire drawing line SLn is thereby corrected to be uniform. In addition, in the local magnification correction in embodiment 1, for the purpose of 1 pixel (1 bit) of each of a plurality of discrete correction points set on the 1-drawing line, the size of the pixel at each correction point drawn on the substrate is slightly expanded or reduced in the main scanning direction by slightly increasing or decreasing the interval of the light spot SP in the main scanning direction from the standard interval (for example, 1/2 of the size Φ of the light spot SP) in the pixel at the correction point.

The polarization beam splitter 34 transmits the S-polarized light and reflects the P-polarized light, and guides the seed light S1 generated by the DFB semiconductor laser device 30 and the seed light S2 generated by the DFB semiconductor laser device 32 to the photoelectric element 36. Specifically, the polarization beam splitter 34 guides the seed light S1 to the electro-optical element 36 by transmitting the seed light S1 of S-polarized light generated by the DFB semiconductor laser device 30. The polarization beam splitter 34 reflects the seed light S2 of the P-polarized light generated by the DFB semiconductor laser device 32 to guide the seed light S2 to the photoelectric device 36. The DFB

semiconductor laser elements

30 and 32 and the polarization beam splitter 34 constitute a pulse light source unit 35 that generates seed lights S1 and S2.

The photoelectric element (intensity modulation section) 36 is transparent to the seed lights S1 and S2, and for example, an Electro-optical Modulator (EOM) is used. The photoelectric element 36 switches the polarization state of the seed lights S1, S2 by the driving circuit 36a in response to the high/low state of the drawing bit string data SBa (SBb). The drawing bit string data SBa is generated based on pattern data (bit patterns) corresponding to patterns to be exposed by the scan cells U1-U3, and the drawing bit string data SBb is generated based on pattern data (bit patterns) corresponding to patterns to be exposed by the scan cells U4-U6. Therefore, the drawing bit string data SBa is input to the driving circuit 36a of the light source device LSa, and the drawing bit string data SBb is input to the driving circuit 36a of the light source device LSb. Since the seed lights S1 and S2 from the DFB semiconductor laser device 30 and the DFB semiconductor laser device 32 have a long wavelength range of 800nm or more, the photoelectric element 36 can be used with a switching response of the polarization state of GHz.

The pattern data (drawing data) is provided for each scanning unit Un, and the pattern drawn by each scanning unit Un is divided by pixels of a size Pxy set according to the size φ of the spot SP, and each of the plurality of pixels is represented by logical information (pixel data) corresponding to the pattern. That is, the pattern data is dot pattern data composed of logical information of a plurality of pixels two-dimensionally decomposed such that a direction along the main scanning direction (Y direction) of the spot SP is a row direction and a direction along the sub-conveying direction (X direction) of the substrate P is a column direction. The logical information of the pixel is 1 bit data of "" 0 "" or "" 1 "". The logical information "0" indicates that the intensity of the spot SP irradiated on the substrate P is set to a low level (not drawn), and the logical information "1" indicates that the intensity of the spot SP irradiated on the substrate P is set to a high level (drawn). The size in the main scanning direction (Y direction) of the pixel size Pxy is Py, and the size in the sub-scanning direction (X direction) is Px.

The logic information of the pixels of 1 line in the pattern data corresponds to 1 drawing line SLn (SL1 to SL 6). Therefore, the number of pixels of 1 line can be determined by the size Pxy of the pixels on the irradiated surface of the substrate P and the length of the drawing line SLn. The dimension Pxy of the 1 pixel is set to be the same as the size phi of the spot SP or larger than the size phi of the spot SP, and for example, when the effective size phi of the spot SP is 3 μm, the dimension Pxy of the 1 pixel is set to be about 3 μm square or larger. The intensity of the spot SP projected onto the substrate P along 1 drawing line SLn (SL1 to SL6) is modulated in accordance with the logical information of 1 line of pixels. The logic information of the pixels of 1 line is referred to as serial data DLn. That is, the pattern data is dot pattern data in which the serial data DLn is arranged in the column direction. The serial data DLn of the pattern data of the scan cell U1 is denoted by DL1, and the serial data DLn of the pattern data of the scan cells U2 to U6 are denoted by DL2 to DL 6.

Since the 3 scan cells U1 to U3(U4 to U6) of the scan module repeat the scanning operation of the spot SP in a specific order, the serial data DL1 to DL3(DL4 to DL6) of the pattern data of the 3 scan cells U1 to U3(U4 to U6) of the scan module are also output to the driving circuit 36a of the light source device lsa (lsb) in a specific order. The serial data DL1 to DL3 sequentially output to the driving circuit 36a of the light source device LSa are referred to as drawing bit string data SBa, and the serial data DL4 to DL6 sequentially output to the driving circuit 36a of the light source device LSb are referred to as drawing bit string data SBb.

For example, when the order of the scanning cells Un for scanning the spot SP in the 1 st scanning module is U1 → U2 → U3, the serial data DL1 of 1 line is first output to the driving circuit 36a of the light source device LSa, the serial data DL2 of 1 line is then output to the driving circuit 36a of the light source device LSa, and the serial data DL1 to DL3 of 1 line constituting the drawing bit serial data SBa are output to the driving circuit 36a of the light source device LSa in the order of DL1 → DL2 → DL 3. Then, the serial data DL1 to DL3 of the next column are output to the driving circuit 36a of the light source device LSa as drawing bit string data SBa in the order of DL1 → DL2 → DL 3. Similarly, when the order of the scanning cells Un for scanning the spot SP in the 2 nd scanning module is U4 → U5 → U6, the serial data DL4 of 1 line is first output to the driving circuit 36a of the light source device LSb, the serial data DL5 of 1 line is then output to the driving circuit 36a of the light source device LSb, and the serial data DL4 to DL6 of 1 line constituting the drawing bit string data SBb are output to the driving circuit 36a of the light source device LSb in the order of DL4 → DL5 → DL 6. Then, the serial data DL4 to DL6 of the next column are output to the driving circuit 36a of the light source device LSb as drawing bit string data SBb in the order of DL4 → DL5 → DL 6. The specific configuration of the driving circuit 36a for outputting the rendering bit string data sba (sbb) to the light source device lsa (lsb) will be described in detail below.

When the logic information of 1 pixel amount of the drawing bit string data sba (sbb) input to the driving circuit 36a is in a low ("" 0 "") state, the photoelectric element 36 directly leads to the polarization beam splitter 38 without changing the polarization state of the light beams S1, S2. On the other hand, when the logic information of 1 pixel amount of the drawing bit string data sba (sbb) input to the driving circuit 36a is in the high ("1") state, the photoelectric element 36 changes the polarization state of the incident seed lights S1, S2, that is, changes the polarization direction by 90 degrees and guides the seed lights to the polarization beam splitter 38. The driving circuit 36a drives the electrooptic element 36 based on the drawing bit string data sba (sbb) in this manner, and the electrooptic element 36 converts the S-polarized seed light S1 into the P-polarized seed light S1 and the P-polarized seed light S2 into the S-polarized seed light S2 when the logic information of the pixel of the drawing bit string data sba (sbb) is in a high state ("" 1 "").

The polarization beam splitter 38 transmits the P-polarized light, guides the light to the combiner 44 through the lens element GL, and reflects the S-polarized light to the absorber 40. The light (seed light) transmitted through the polarization beam splitter 38 is represented by a light beam Lse. The oscillation frequency of the pulsed light beam Lse becomes Fa. The excitation light source 42 generates excitation light, which is guided to the combiner 44 through the optical fiber 42 a. The combiner 44 combines the light beam Lse irradiated from the polarization beam splitter 38 with the excitation light, and outputs the resultant to the fiber optical amplifier 46. The fiber optic amplifier 46 is doped with a lasing medium that is excited by the excitation light. Therefore, in the fiber optical amplifier 46 through which the combined light beam Lse and excitation light are transmitted, the laser medium is excited by the excitation light, and the light beam Lse as seed light is amplified. As a laser medium doped in the fiber optical amplifier 46, a rare earth element such as erbium (Er), ytterbium (Yb), thulium (Tm), or the like is used. The amplified light beam Lse is radiated from the exit end 46a of the fiber optical amplifier 46 with a specific divergence angle, converged or collimated by the lens element GL, and incident to the wavelength conversion optical element 48.

The wavelength conversion optical element (1 st wavelength conversion optical element) 48 converts the incident light beam Lse (wavelength λ) into the 2 nd Harmonic of 1/2 having a wavelength λ by means of 2 nd Harmonic Generation (SHG). As the wavelength converting optical element 48, a PPLN (periodic Poled LiNbO3) crystal as a Quasi-Phase Matching (QPM) crystal is preferably used. Further, a PPLT (periodic Poled LiTaO3) crystal or the like can also be used.

The wavelength conversion optical element (2 nd wavelength conversion optical element) 50 generates a3 rd harmonic of 1/3 having a wavelength of λ by Sum Frequency Generation (SFG) of the 2 nd harmonic (wavelength λ/2) converted by the wavelength conversion optical element 48 and seed light (wavelength λ) remaining without being converted by the wavelength conversion optical element 48. The 3 rd harmonic is ultraviolet light (beam LB) having a peak wavelength in a wavelength band of 370mm or less (for example, 355 nm).

As shown in fig. 8, when the logic information for 1 pixel of the drawing bit string data sba (sbb) applied to the driving circuit 36a is low ("" 0 ""), the photoelectric element (intensity modulation section) 36 is directly guided to the polarization beam splitter 38 without changing the polarization state of the incident seed lights S1, S2. Therefore, the light beam Lse transmitted by the polarization beam splitter 38 becomes seed light S2. Therefore, the P-polarized light lba (lbb) finally outputted from the light source device lsa (lsb) has the same oscillation distribution (temporal characteristics) as the seed light S2 from the DFB semiconductor laser element 32. That is, in this case, the light beam lba (lbb) is characterized by a lower peak intensity of the pulse and a broad passivation in time. The optical fiber amplifier 46 has a low amplification efficiency with respect to the seed light S2 with a low peak intensity, and thus the light beam lba (lbb) emitted from the light source device lsa (lsb) becomes light that is not amplified to the energy required for exposure. Therefore, from the viewpoint of exposure, the light source device lsa (lsb) does not emit the light beam lba (lbb) with substantially the same result. That is, the intensity of the spot SP irradiated on the substrate P becomes low. However, during the period in which the pattern is not exposed (non-exposure period), the light beam lba (lbb) of the ultraviolet region from the seed light S2 is continuously irradiated although it has a minute intensity. Therefore, when the drawing lines SL1 to SL6 are maintained at the same positions on the substrate P for a long time (for example, when the substrate P stops due to a failure of the conveyance system), it is preferable to close the emission windows by providing movable shutters in the emission windows (not shown) of the light beams lba (lbb) of the light source devices lsa (lsb).

On the other hand, as shown in fig. 8, when the logic information for 1 pixel of the drawing bit string data sba (sbb) applied to the driving circuit 36a is high ("" 1 ""), the photoelectric element (intensity modulation section) 36 changes the polarization state of the incident seed lights S1, S2 and guides the seed lights to the polarization beam splitter 38. Therefore, the light beam Lse transmitted by the polarization beam splitter 38 becomes seed light S1. Therefore, the light beam lba (lbb) emitted from the light source device lsa (lsb) is generated from the seed light S1 from the DFB semiconductor laser element 30. Since the seed light S1 from the DFB semiconductor laser device 30 has a strong peak intensity, it is efficiently amplified by the fiber optical amplifier 46, and the light beam lba (lbb) of P-polarized light output from the light source device lsa (lsb) has energy required for exposure of the substrate P. That is, the intensity of the spot SP irradiated on the substrate P becomes high.

In this way, since the photo-electric element 36 as a light modulator for drawing is provided in the light source device lsa (lsb), the intensity of the light spot SP scanned by the 3 scanning units U1 to U3(U4 to U6) of the scanning module can be modulated in accordance with the pattern to be drawn by controlling 1 photo-electric element (intensity modulation section) 36. Therefore, the light beam lba (lbb) emitted from the light source device lsa (lsb) becomes the intensity modulated tracing light beam.

In the configuration of fig. 7, it is also conceivable to omit the DFB semiconductor laser element 32 and the polarization beam splitter 34, and to guide only the seed light S1 from the DFB semiconductor laser element 30 into the optical fiber amplifier 46 in the form of an explosion light waveform by switching the polarization state of the photoelectric element 36 based on the pattern data (the drawing bit string data SBa, SBb, or the string data DLn). However, with this configuration, the incident periodicity of the seed light S1 to the optical fiber amplifier 46 is greatly disturbed by the pattern to be drawn. That is, if the seed light S1 enters the optical fiber amplifier 46 after the state where the seed light S1 from the DFB semiconductor laser element 30 does not enter the optical fiber amplifier 46 continues, the following problems occur: the seed light S1 immediately after incidence is amplified at a larger amplification factor than usual, and a light beam (giant pulse) having a large intensity equal to or higher than a predetermined value is generated from the optical fiber amplifier 46 in several pulses. Therefore, in the present embodiment 1, it is preferable that the seed light S2 (wide pulse light with low peak intensity) from the DFB semiconductor laser element 32 is made to enter the optical fiber amplifier 46 while the seed light S1 does not enter the optical fiber amplifier 46, thereby solving the above-described problem.

Further, the photoelectric element 36 is switched, but the DFB

semiconductor laser elements

30, 32 may be driven based on pattern data (drawing bit string data SBa, SBb, or serial data DLn). In this case, the DFB

semiconductor laser elements

30 and 32 function as a drawing light modulator (intensity modulation section). That is, the control circuit 22 controls the DFB

semiconductor laser elements

30 and 32 based on the drawing bit string data SBa (DL1 to DL3) and SBb (DL4 to DL6) to selectively (alternatively) generate the seed lights S1 and S2 oscillating in a pulse shape at the specific frequency Fa. In this case, one of the seed lights S1, S2 selectively pulsed from either of the DFB

semiconductor laser elements

30, 32 is directly incident on the combiner 44 without the need for the

polarization beam splitters

34, 38, the photoelectric element 36, and the absorber 40. At this time, the control circuit 22 controls the drive of the DFB

semiconductor laser elements

30 and 32 so that the seed light S1 from the DFB semiconductor laser element 30 and the seed light S2 from the DFB semiconductor laser element 32 are not incident on the optical fiber amplifier 46 at the same time. That is, when the spot SP of each beam LBn is irradiated on the substrate P, the DFB semiconductor laser device 30 is controlled so that only the seed light S1 enters the fiber optical amplifier 46. When the spot SP of each beam LBn is not irradiated on the substrate P (the intensity of the spot SP is made extremely low), the DFB semiconductor laser element 32 is controlled so that only the seed light S2 enters the fiber optical amplifier 46. Whether or not to irradiate light beam LBn on substrate P is determined based on the logic information (high/low) of the pixel. In this case, the polarization states of the seed lights S1 and S2 may be P-polarized lights.

Here, the light source device lsa (lsb) emits the light beams lba (lbb) such that N light spots SP are projected in the main scanning direction for 1 pixel of the size Pxy on the irradiated surface of the substrate P in the scanning of the light spots SP (in the present embodiment, N is 2). The light beam lba (lbb) emitted from the light source device lsa (lsb) is generated in response to the clock pulse of the clock signal LTC generated by the signal generating unit 22 a. Therefore, in order to project N (N may be an integer of 2 or more) spots SP for 1 pixel of the size Pxy, when the relative scanning speed of the spot SP with respect to the substrate P in the main scanning direction is Vs, the signal generating unit 22a must generate a clock pulse of the clock signal LTC at a reference period Ta (1/Fa) determined by Pxy/(N × Vs) or Py/(N × Vs). For example, when the effective scanning line SLn is 30mm long and the scanning time Tsp of 1 time is about 50 μ sec, the scanning speed Vs of the spot SP is about 600 m/sec. When the pixel size Pxy (Px and Py) is 3 μm, which is the same as the effective size of the spot SP, and N is 2, the reference period Ta becomes 3 μm/(2 × 600m/sec) 0.0025 μ sec, and the frequency Fa (1/Ta) becomes 400 MHz.

The correction position information (set value) Nv of the local magnification correction information CMgn (CMg1 to CMg6) can be arbitrarily changed, and is appropriately set in accordance with the magnification of the drawing line SLn. For example, the corrected position information Nv may be set so that the number of corrected pixels located on the drawing line SLn is 1. The drawing line SL can also be expanded and contracted by the entire magnification correction information TMg, but the local magnification correction can be made finer and finer magnification correction. For example, when the oscillation frequency Fa is 400MHz and the initial value of the scanning length (the drawing range) of the drawing line SLn is 30mm, when the scanning length of the drawing line SLn is extended or contracted by 15 μm (the ratio 500ppm) by the entire magnification correction information TMg, the oscillation frequency Fa must be increased or decreased by about 0.2MHz (the ratio 500ppm), and the adjustment thereof is difficult. Even if the adjustment is possible, the oscillation frequency Fa after the adjustment is switched to with a fixed delay (time constant), and therefore, a desired magnification cannot be obtained therebetween. Further, when the correction ratio of the rendering magnification is set to 500ppm or less, for example, about several ppm to several tens ppm, the local magnification correction method of increasing or decreasing the number of light points in the discrete correction pixels can easily perform correction with a higher resolution than the entire magnification correction method of changing the oscillation frequency Fa of the light source device lsa (lsb). Of course, if both the entire magnification correction method and the partial magnification correction method are used in combination, there is an advantage that correction with a high resolution can be realized while a correction ratio corresponding to a large drawing magnification is obtained.

Fig. 9 is a block diagram showing an electrical configuration of the exposure apparatus EX. The control device 16 of the exposure apparatus EX includes a polygon mirror drive control unit 100, a selective element drive control unit 102, a light beam control device 104, a mark position detection unit 106, and a rotational position detection unit 108. Further, the origin signals SZn (SZ1 to SZ6) output from the origin sensors OPn (OP1 to OP6) of the scanning units Un (U1 to U6) are input to the polygon mirror drive control unit 100 and the selection element drive control unit 102. In the example shown in fig. 9, the light beam lba (lbb) from the light source device lsa (lsb) is diffracted by the optical element for selection AOM2(AOM5), and 1 time of diffracted light, i.e., the light beam LB2(LB5), is incident on the scanning unit U2 (U5).

The polygon mirror drive control section 100 drive-controls the rotation of the polygon mirror PM of each scanning unit Un (U1 to U6). The polygon mirror drive control unit 100 includes a rotation drive source (a motor, a speed reducer, or the like) RM that drives the polygon mirror PM of each scanning unit Un (U1 to U6), and drives and controls the rotation of the polygon mirror PM by driving and controlling the rotation of the motor. The polygon mirror drive control unit 100 synchronously rotates the polygon mirror PM of the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module so that the rotational angle positions of the polygon mirror PM of the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module have a specific phase relationship. That is, the polygon mirror drive control section 100 controls the rotation of the polygon mirror PM of the plurality of scanning units Un (U1 to U6) in such a manner that the rotational speeds (the numbers of rotations) Vp of the polygon mirror PM of the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning module are the same with each other, and the phases of the rotational angle positions are shifted by a fixed angle amount at a time. The rotational speed Vp of the polygon mirror PM of each scanning unit Un (U1 to U6) is the same.

In embodiment 1, since the rotation angle α of the polygon mirror PM contributing to actual scanning is set to 15 degrees as described above, the scanning efficiency of the polygon mirror PM having an octagonal shape with 8 reflection surfaces RP becomes 1/3. In the 1 st scan block, scanning based on the spot SP of the 3 scan cells Un is performed in the order of U1 → U2 → U3. Therefore, the polygon mirror PM of each of the scanning units U1 to U3 is synchronously controlled by the polygon mirror drive control unit 100 so as to rotate at a constant speed while the phase of the rotational angle position of the polygon mirror PM of each of the 3 scanning units U1 to U3 is shifted by 15 degrees in this order. In the 2 nd scan block, the scanning of the spot SP by the 3 scan cells Un is performed in the order of U4 → U5 → U6. Therefore, the polygon mirror PM of each of the scanning units U4 to U6 is synchronously controlled by the polygon mirror drive control unit 100 so as to rotate at a constant speed while the phase of the rotational angle position of the polygon mirror PM of each of the 3 scanning units U4 to U6 is shifted by 15 degrees in this order.

Specifically, as shown in fig. 10, the polygon mirror drive control section 100 controls the rotational phase of the polygon mirror PM of the scanning unit U2 for the 1 st scanning module, for example, in such a manner that the origin signal SZ2 from the origin sensor OP2 of the scanning unit U2 is generated with a delay time Ts with reference to the origin signal SZ1 from the origin sensor OP1 of the scanning unit U1. The polygon mirror drive control section 100 controls the rotational phase of the polygon mirror PM of the scanning unit U3 in such a manner that the origin signal SZ3 from the origin sensor OP3 of the scanning unit U3 is generated with a delay of 2 × time Ts with reference to the origin signal SZ 1. The time Ts is a time during which the polygon mirror PM rotates by 15 degrees (maximum scanning time of the spot SP). Thereby, the phase difference of the rotational angle position of the polygon mirror PM in each of the scanning units U1 to U3 is shifted by 15 degrees in the order of U1, U2, and U3. Therefore, the 3 scan cells U1 to U3 of the 1 st scan module can scan the spot SP in the order of U1 → U2 → U3.

Similarly, in the 2 nd scanning module, the polygon mirror drive control section 100 controls the rotational phase of the polygon mirror PM of the scanning unit U5 such that the origin signal SZ5 from the origin sensor OP5 of the scanning unit U5 is delayed by the time Ts with reference to the origin signal SZ4 from the origin sensor OP4 of the scanning unit U4. The polygon mirror drive control section 100 controls the rotational phase of the polygon mirror PM of the scanning unit U6 in such a manner that the origin signal SZ6 from the origin sensor OP6 of the scanning unit U6 is generated with a delay of 2 × time Ts with reference to the origin signal SZ 4. Thereby, the phases of the rotational angle positions of the polygon mirrors PM of the scanning units U4 to U6 are shifted by 15 degrees in the order of U4, U5, and U6. Therefore, the 3 scan cells Un (U4 to U6) of the 2 nd scan module can scan the spot SP in the order of U4 → U5 → U6.

The selecting element drive controller (beam switching drive controller) 102 controls the selecting optical elements AOMn (AOM1 to AOM3, AOM4 to AOM6) of each optical element block of the beam switching unit BDU, and sequentially distributes the light beams LB (LBa, LBb) from the light source devices LS (LSa, LSb) to the 3 scanning units Un (U1 to U3, U4 to U6) of each scanning block after the 1 scanning unit Un of each scanning block starts scanning of the light spot SP until the next scanning is started. After the start of scanning of the spot SP by 1 scanning unit Un until the start of the next scanning, the polygon mirror PM rotates by 45 degrees, and the time interval thereof becomes a time Tpx (═ 3 × Ts).

Specifically, when the origin signal SZn (SZ1 to SZ6) is generated, the selective element drive control unit 102 generates the origin signal SZn, and then applies the drive signal (high frequency signal) HFn (HF1 to HF6) to the selective optical elements AOMn (AOM1 to AOM6) corresponding to the scanning units Un (U1 to U6) that generate the origin signal SZn (SZ1 to SZ6) for a fixed time (on time Ton). Thus, the optical element AOMn for selection to which the drive signal (high-frequency signal) HFn is applied is turned on for the on time Ton, and the light beam LBn can be incident on the corresponding scanning cell Un. Further, since the light beam LBn is incident on the scanning cell Un that generates the origin signal SZn, the light beam LBn can be incident on the scanning cell Un that can scan the spot SP. The on time Ton is a time equal to or shorter than time Ts.

The origin signals SZ1 to SZ3 generated in the 3 scan cells U1 to U3 of the 1 st scan module are generated in the order of SZ1 → SZ2 → SZ3 at time Ts intervals. Therefore, the drive signals (high-frequency signals) HF1 to HF3 are applied to the optical elements AOM1 to AOM3 for selection of the 1 st optical element module for the on time Ton in the order of AOM1 → AOM2 → AOM3 at the time Ts interval. Accordingly, the 1 st optical element module (AOM1 to AOM3) can switch 1 scanning unit Un on which the light beam LBn (LB1 to LB3) from the light source device LSa is incident in the order of U1 → U2 → U3 at time Ts intervals. Thereby, the scanning unit Un that scans the spot SP is switched in the order of U1 → U2 → U3 at the time Ts interval. At a time (Tpx is 3 × Ts) after the scanning unit U1 starts scanning with the spot SP until the next scanning starts, the light beam LBn (LB1 to LB3) from the light source device LSa may be sequentially incident on any of the 3 scanning units Un (U1 to U3).

Similarly, the origin signals SZ4 to SZ6 generated in the 3 scan cells U4 to U6 of the 2 nd scan module are generated in the order of SZ4 → SZ5 → SZ6 at time Ts intervals. Therefore, the drive signals (high-frequency signals) HF4 to HF6 are applied to the optical elements for selection AOM4 to AOM6 of the 2 nd optical element module for selection at the time Ts intervals for the on time Ton in the order of AOM4 → AOM5 → AOM 6. Accordingly, the 2 nd optical element module (AOM4 to AOM6) can switch 1 scanning unit Un on which the light beam LBn (LB4 to LB6) from the light source device LSb is incident in the order of U4 → U5 → U6 at time Ts intervals. Thereby, the scanning unit Un that scans the spot SP is switched in the order of U4 → U5 → U6 at the time Ts interval. At a time (Tpx is 3 × Ts) after the scanning unit U4 starts scanning with the spot SP until the next scanning starts, the light beam LBn (LB4 to LB6) from the light source device LSb may be sequentially incident on any of the 3 scanning units Un (U4 to U6).

To explain the selective element drive control unit 102 in more detail, when the origin signal SZn (SZ1 to SZ6) is generated, the selective element drive control unit 102 generates the origin signal SZn (SZ1 to SZ6) and then generates a plurality of incidence enable signals LPn (LP1 to LP6) that become H (high) for a fixed time (on time Ton) as shown in fig. 10. The plurality of incident permission signals LPn (LP1 to LP6) are signals that permit the corresponding selection optical elements AOMn (AOM1 to AOM6) to be turned on. That is, the incidence permission signals LPn (LP1 to LP6) are signals that permit the light beam LBn (LB1 to LB6) to be incident on the corresponding scan cell Un (U1 to U6). The selective element drive control unit 102 applies drive signals (high frequency signals) HFn (HF1 to HF6) to the corresponding selective optical elements AOMn (AOM1 to AOM6) for the on time Ton during which the incident permission signals LPn (LP1 to LP6) become H (high), and sets the corresponding selective optical elements AOMn to an on state (a state in which 1-time diffracted light is generated). For example, the selective element drive control unit 102 applies the drive signals HF1 to HF3 to the corresponding selective optical elements AOM1 to AOM3 for a fixed time Ton during which the incident enable signals LP1 to LP3 are H (high). Thereby, the light beams LB1 to LB3 from the light source device LSa are incident on the corresponding scanning units U1 to U3. The selective element drive control unit 102 applies drive signals (high frequency signals) HF4 to HF6 to the corresponding selective optical elements AOM4 to AOM6 for a fixed time Ton during which the incident enable signals LP4 to LP6 are H (high). Thereby, the light beams LB4 to LB6 from the light source device LSb are incident on the corresponding scanning units U4 to U6.

As shown in fig. 10, the incident enable signals LP1 to LP3 corresponding to the 3 selection optical elements AOM1 to AOM3 of the 1 st optical element module are shifted by the time Ts at the rising timing of H (high) in the order of LP1 → LP2 → LP3, and the on times Ton of H (high) do not overlap each other. Therefore, the scanning unit Un on which the light beam LBn (LB1 to LB3) is incident is switched in the order of U1 → U2 → U3 at time Ts intervals. Similarly, the rise timings of the incident enable signals LP4 to LP6 corresponding to the 3 selection optical elements AOM4 to AOM6 of the 2 nd optical element module are shifted by the time Ts in the order of LP4 → LP5 → LP6, and the on times Ton of H (high) do not overlap each other. Therefore, the scanning unit Un on which the light beam LBn (LB4 to LB6) is incident is switched in the order of U4 → U5 → U6 at time Ts intervals. The selection element drive control unit 102 outputs the generated plurality of incidence permission signals LPn (LP1 to LP6) to the light flux controlling device 104.

The beam control device (beam control unit) 104 shown in fig. 9 controls the light emission frequency Fa of the beam LB (LBa, LBb, LBn), the magnification of the drawing line SLn drawn by the spot SP of the beam LB, and the intensity modulation of the beam LB. The beam control apparatus 104 includes a whole magnification setting unit 110, a local magnification setting unit 112, a drawing data output unit 114, and an exposure control unit 116. The entire magnification setting unit (entire magnification correction information storage unit) 110 is a signal generation unit 22a that stores the entire magnification correction information TMg transmitted from the exposure control unit 116 and outputs the entire magnification correction information TMg to the control circuit 22 of the light source device LS (LSa, LSb). The clock generation unit 60 of the signal generation unit 22a generates the clock signal LTC of the oscillation frequency Fa corresponding to the entire magnification correction information TMg. The detailed configurations of the overall magnification setting unit 110 and the local magnification setting unit 112 will be described in detail below.

The local magnification setting unit (local magnification correction information storage unit, correction information storage unit) 112 is a signal generation unit 22a that stores the local magnification correction information (correction information) CMgn transmitted from the exposure control unit 116, and outputs the local magnification correction information CMgn to the control circuit 22 of the light source device LS (LSa, LSb). Based on the local magnification correction information CMgn, the position of the correction pixel on the drawing line SLn is specified (specified), and the magnification is determined. The signal generating unit 22a of the control circuit 22 outputs pixel shift pulses BSC (BSCa, BSCb) based on the correction pixels and the magnifications thereof determined based on the local magnification correction information CMg. The local magnification setting unit 112 stores local magnification correction information CMgn (CMg1 to CMg6) for each scan unit Un (U1 to U6) transmitted from the exposure control unit 116. Then, the local magnification setting unit 112 outputs the local magnification correction information CMgn corresponding to the scanning unit Un that scans the spot SP to the signal generating unit 22a of the light source device LS (LSa, LSb). That is, the local magnification setting unit 112 is a signal generating unit 22a that outputs the local magnification correction information CMgn corresponding to the scanning unit Un that generates the origin signal SZn (SZ1 to SZ6) to the light source device LSa (LSa, LSb) that is the generation source of the light beam LBn incident on the scanning unit Un. The correction of the drawing magnification based on the entire magnification correction information TMg or the local magnification correction information CMgn is performed by partially fine-adjusting the clock cycle of the clock signal LTC from the signal generating unit 22a of the control circuit 22 of the light source device LS (LSa, LSb). The detailed configuration of the control circuit 22 (signal generating unit 22a) will be described in detail below.

For example, when the scanning cell Un that generates the origin signal SZn (i.e., the scanning cell Un that scans the spot SP next) is any of the scanning cells U1 to U3, the local magnification setting unit 112 outputs the local magnification correction information CMgn corresponding to the scanning cell Un that generates the origin signal SZn to the signal generating unit 22a of the light source device LSa. Similarly, when the scan cell Un that generates the origin signal SZn is any one of the scan cells U4 to U6, the local magnification setting unit 112 outputs the local magnification correction information CMgn corresponding to the scan cell Un that generates the origin signal SZn to the signal generating unit 22a of the light source device LSb. Thus, the pixel shift pulses BSC (BSCa, BSCb) corresponding to the scanning cells Un (U1 to U3, U4 to U6) that scan the light spot SP for each scanning block are output from the delivery timing switching section 64 of the light source device LS (LSa, LSb). Thus, the scanning length can be individually adjusted for each scanning line SLn.

The drawing data output unit 114 outputs the serial data DLn of 1 line corresponding to the scanning cell Un (scanning cell Un to be scanned with the spot SP next) that generates the origin signal SZn among the 3 scanning cells Un (U1 to U3) of the 1 st scanning module as the drawing bit string data SBa to the drive circuit 36a of the light source device LSa. The drawing data output unit 114 outputs the serial data DLn (DL4 to DL6) of 1 line corresponding to the scanning cell Un (scanning cell Un to be scanned with the spot SP next) that generates the origin signal SZn among the 3 scanning cells Un (U4 to U6) of the 2 nd scanning module as the drawing bit string data SBb to the drive circuit 36a of the light source device LSb. In the 1 st scan module, since the order of the scan cells U1 to U3 for scanning the spot SP is U1 → U2 → U3, the drawing data output unit 114 outputs the serial data DL1 to DL3 repeated in the order of DL1 → DL2 → DL3 as the drawing bit string data SBa. In the 2 nd scan module, since the order of the scan cells U4 to U6 for scanning the spot SP is U4 → U5 → U6, the drawing data output unit 114 outputs the serial data DL4 to DL6 repeated in the order of DL4 → DL5 → DL6 as the drawing bit string data SBb.

The exposure control unit 116 shown in fig. 9 controls the entire magnification setting unit 110, the local magnification setting unit 112, and the drawing data output unit 114. The exposure control unit 116 receives position information of the installation orientation line Lx1 detected by the mark position detection unit 106, position information of the alignment marks MKm (MK1 to MK4) on the Lx4, and rotation angle position information of the rotary drum DR on the installation orientation lines Lx1 to Lx4 detected by the rotation position detection unit 108 (count values based on the counter circuits CN1a to CN4a, CN1b to CN4 b). The exposure control unit 116 detects (determines) the start position of the drawing exposure of the exposure field W in the sub-scanning direction (X direction) of the substrate P based on the position information of the alignment mark MKm (MK1 to MK4) on the set azimuth line Lx1 and the rotation angle position of the rotary drum DR on the set azimuth line Lx1 (the count values of the counter circuits CN1a, CN1 b).

The exposure control unit 116 determines whether or not the start position of the drawing exposure of the substrate P has been carried to the drawing lines SL1, SL3, and SL5 located on the set orientation line Lx2, based on the rotational angle position of the rotary drum DR on the set orientation line Lx1 and the rotational angle position on the set orientation line Lx2 (based on the count values of the counter circuits CN2a and CN2 b) at the time of detecting the start position of the drawing exposure. If it is determined that the start position of the drawing exposure has been transferred to the drawing lines SL1, SL3, and SL5, the exposure control unit 116 controls the local magnification setting unit 112, the drawing data output unit 114, and the like to start the drawing by the scanning of the spot SP by the scanning units U1, U3, and U5.

In this case, the exposure control unit 116 causes the local magnification setting unit 112 to output the local magnification correction information CMg1 and CMg3 corresponding to the scanning units U1 and U3 that scan the spot SP to the signal generating unit 22a of the light source device LSa at the timing when the scanning units U1 and U3 perform the drawing exposure. Thus, the signal generating unit 22a of the light source device LSa generates the pixel shift pulse BSCa for shifting the pixels of the serial data DL1 and DL3 of the scanning cells U1 and U3 for scanning the spot SP, based on the local magnification correction information CMg1 and CMg 3. The drawing data output section 114 shifts the logic information of each pixel of the serial data DL1 and DL3 corresponding to the scanning cells U1 and U3 for scanning the spot SP, pixel by pixel, in accordance with the pixel shift pulse BSCa. Similarly, the exposure control unit 116 is configured to cause the local magnification setting unit 112 to output the local magnification correction information CMg5 corresponding to the scanner unit U5 to the signal generating unit 22a of the light source device LSb at the timing when the scanner unit U5 performs the drawing exposure. Thus, the signal generating section 22a of the light source device LSb generates the pixel shift pulse BSCb for shifting the pixels of the serial data DL5 corresponding to the scanning cell U5 for scanning the spot SP, based on the local magnification correction information CMg 5. Based on the pixel shift pulse BSCb, the drawing data output section 114 shifts the logic information of each pixel of the serial data DL5 of the scanning unit U5, which performs scanning of the light spot SP, pixel by pixel.

Then, the exposure control unit 116 determines whether or not the start position of the drawing exposure of the substrate P has been carried to the drawing lines SL2, SL4, and SL6 located on the set orientation line Lx3, based on the rotational angle position of the rotary drum DR on the set orientation line Lx1 and the rotational angle position (the count value of the counter circuits CN3a, CN3 b) on the set orientation line Lx3 at the time of detecting the start position of the drawing exposure. If it is determined that the start position of the drawing exposure has been transferred to the drawing lines SL2, SL4, and SL6, the exposure control unit 116 controls the local magnification setting unit 112 and the drawing data output unit 114, and causes the scanning units U2, U4, and U6 to start scanning of the spot SP.

In this case, the exposure control unit 116 causes the local magnification setting unit 112 to output the local magnification correction information CMg2 corresponding to the scanning unit U2 that scans the spot SP to the signal generating unit 22a of the light source device LSa at the timing when the scanning unit U2 performs the drawing exposure. Thus, the signal generating section 22a of the light source device LSa generates the pixel shift pulse BSCa for shifting the pixels of the serial data DL2 of the scanning unit U2 for scanning the spot SP, based on the local magnification correction information CMg 2. Based on the pixel shift pulse BSCa, the drawing data output section 114 shifts the logic information of each pixel of the serial data DL2 of the scanning cell U2, which performs scanning of the spot SP, pixel by pixel. Similarly, the exposure control unit 116 causes the local magnification setting unit 112 to output the local magnification correction information CMg4 and CMg6 corresponding to the scanner units U4 and U6 to the signal generating unit 22a of the light source device LSb at the timing when the scanner units U4 and U6 perform the drawing exposure. Thus, the signal generating unit 22a of the light source device LSb generates the pixel shift pulse BSCb for shifting the pixels of the serial data DL4 and DL6 of the scanning cells U4 and U6 for scanning the spot SP, based on the local magnification correction information CMg4 and CMg 6. The drawing data output section 114 shifts the logic information of each pixel of the serial data DL4 and DL6 of the scanning cells U4 and U6, which perform scanning of the light spot SP, pixel by pixel in accordance with the pixel shift pulse BSCb.

As is clear from fig. 4, since the substrate P is transported in the + X direction, the drawing exposure is performed on each of the drawing lines SL1, SL3, and SL5 first, and after the substrate P is transported a certain distance, the drawing exposure is performed on each of the drawing lines SL2, SL4, and SL 6. On the other hand, since the respective polygon mirrors PM of the 3 scanning units U1 to U3 of the 1 st scanning module and the respective polygon mirrors PM of the 3 scanning units U4 to U6 of the 2 nd scanning module are rotation-controlled with a specific phase difference, the origin signals SZ1 to SZ3 and SZ4 to SZ6 are continuously generated with a phase difference over a time Ts as shown in fig. 10. Therefore, the incident permission signals LPn (LP1 to LP6) shown in fig. 10 are generated, and the serial data DL2, DL4, and DL6 are also output during a period from the start time point of the drawing exposure on the drawing lines SL1, SL3, and SL5 to immediately before the drawing exposure on the drawing lines SL2, SL4, and SL6 starts. Therefore, before the start position of the drawing exposure of the exposure field W reaches the drawing lines SL2, SL4, and SL6, a pattern is drawn by scanning the spot SP by the scanning units U2, U4, and U6. Therefore, the exposure control unit 116 in fig. 9 inhibits the shift of the pixels of the serial data DL2, DL4, and DL6 corresponding to each of the scan cells U2, U4, and U6 by the logic circuit that performs a logical operation on the incident permission signals LPn (LP1 to LP 6).

The exposure control unit 116 calculates the strain (deformation) of the substrate P or the exposure field W sequentially based on the position information of the alignment marks MKm (MK1 to MK4) on the installation orientation line Lx1 and Lx4 detected by the mark position detection unit 106 and the rotation angle position information of the rotating drum DR on the installation orientation lines Lx1 and Lx4 detected by the rotation position detection unit 108. For example, when the substrate P is subjected to a large tension in the longitudinal direction or is deformed by a thermal process, the shape of the exposed area W is also strained (deformed), and the alignment marks MKm (MK1 to MK4) are not arranged in a rectangular shape as shown in fig. 4, but are in a state of being strained (deformed). When the substrate P or the exposure area W is strained, the magnification of each of the drawing lines SLn must be changed in accordance with the strain, and therefore the exposure control unit 116 generates at least one of the entire magnification correction information TMg and the local magnification correction information CMgn based on the calculated strain of the substrate P or the exposure area W. Then, at least one of the generated total magnification correction information TMg and local magnification correction information CMgn is output to the total magnification setting unit 110 or local magnification setting unit 112. Therefore, the precision of the overlapping exposure can be improved.

Further, the exposure control section 116 may generate the corrected inclination angle information for each of the drawing lines SLn in accordance with the strain of the substrate P or the exposed area W. Based on the generated corrected tilt angle information, the above-described actuators rotate the respective scanning units Un (U1 to U6) about the irradiation center axes Len (Le1 to Le 6). Thereby, the precision of the overlay exposure is further improved. The exposure control unit 116 may generate again at least one of the entire magnification correction information TMg and the local magnification correction information CMgn and the corrected tilt angle information each time the scanning unit Un (U1 to U6) scans the spot SP, each time the scanning unit Un scans the spot SP a predetermined number of times, or each time the tendency of the strain of the substrate P or the exposed area W changes beyond an allowable range.

Fig. 11 is a diagram showing the configuration of the signal generating unit 22a provided inside the light source device lsa (lsb). As shown in fig. 9, local magnification correction information CMgn including correction position information Nv and expansion/contraction information (polarity information) POL is transmitted from local magnification setting unit 112 to signal generating unit 22 a. The local magnification setting unit 112 stores local magnification correction information CMgn (CMg1 to CMg6) for each scan cell Un (U1 to U6).

The signal generating section 22a includes a clock signal generating section 200, a correction point designating section 202, and a clock switching section 204. The clock signal generating section 200, the correction point designating section 202, and the clock switching section 204 can be configured by being integrated by an FPGA (Field Programmable Gate Array). The clock signal generating unit 200 generates a plurality of (N) clock signals CKp (p is 0, 1, 2, …, N-1) having a reference period Te shorter than a period defined by Φ/Vs and giving a phase difference in units of a correction time of 1/N of the reference period Te. Phi is the effective size of the spot SP, and Vs is the relative speed of the spot SP with respect to the main scanning direction of the substrate P, and the description will be given with 150mm/sec as an example. When the reference period Te is longer than the period defined by Φ/Vs, the light spots SP irradiated in the main scanning direction are discretely irradiated onto the irradiated surface of the substrate P at a predetermined interval. On the contrary, when the reference period Te is shorter than the period defined by Φ/Vs, the light spots SP are irradiated onto the irradiated surface of the substrate P so as to overlap each other in the main scanning direction. In the present embodiment, in principle, the oscillation frequency Fe is set to 100MHz for overlapping the light spot SP with 1/2 of the size Φ each time. In this case, the reference period Te is set to a value smaller than 1/Fe 1/100 [ MHz ] - [ 10 [ nsec ] - [ 3 [ μm ] - [ 150 [ mm/sec ] - [ 20nsec ] - [ Vs ]. When N is 50, the clock signal generation unit 200 generates 50 clock signals CK0 to CK49 to which a phase difference of 0.2nsec (10 [ nsec ]/50) is added.

Specifically, the clock signal generating section 200 includes a clock generating section (oscillator) 60 and a plurality of (N-1) delay circuits De (De01 to De 49). The clock generation unit 60 generates a clock signal CK0 composed of clock pulses oscillating at an oscillation frequency Fe (═ 1/Te) corresponding to the entire magnification correction information TMg. In the present embodiment, the entire magnification correction information TMg is set to 0 (correction amount 0%), and the clock generation unit 60 generates the clock signal CK0 at an oscillation frequency Fe of 100MHz (reference period Te is 10 nsec).

The clock signal (output signal) CK0 from the clock generating unit 60 is input to the delay circuit De01 at the beginning (head) of the plurality of delay circuits De (De01 to De49) connected in series, and is input to the 1 st input terminal of the clock switching unit 204. The delay circuit De (De01 to De049) delays the clock signal CKp as an input signal by a fixed time (Te/N is 0.2nsec) and outputs the delayed clock signal CKp. Therefore, the first stage delay circuit De01 outputs a clock signal (output signal) CK1, which is the same reference period Te (10nsec) as the clock signal CK0 generated by the clock generation unit 60 and has a delay of 0.2nsec with respect to the clock signal CK0 (output signal) CK 1. Similarly, the 2 nd stage delay circuit De02 outputs a clock signal (output signal) CK2, and the clock signal (output signal) CK2 is the same reference cycle Te (10nsec) as the clock signal (output signal) CK1 from the previous stage delay circuit De01 and has a delay of 0.2nsec with respect to the clock signal CK 1. The delay circuits De03 to De49 in the 3 rd stage and later stage similarly output clock signals (output signals) CK3 to CK49, the clock signals (output signals) CK3 to CK49 being the same reference period Te (10nsec) as the clock signals (output signals) CK2 to CK48 from the delay circuits De02 to De48 in the preceding stage, and having a delay of 0.2nsec with respect to the clock signals CK2 to CK 48.

Since the clock signals CK0 to CK49 are signals to which a phase difference is given every 0.2nsec, the clock signal CK0 is a signal that is shifted by exactly 1 cycle from a clock signal that is the same reference cycle Te (10nsec) as the clock signal CK49 and has a delay of 0.2nsec with respect to the clock signal CK 49. Therefore, the clock signal CK0 can be regarded as a clock signal delayed by 0.2nsec from each clock pulse of the clock signal CK 49. Clock signals CK1 to CK49 from the delay circuits De01 to De49 are input to the 2 nd to 50 th input terminals of the clock switching unit 204.

The clock switching unit 204 is a multiplexer (selection circuit) that selects any one of the input 50 clock signals CKp (CK0 to CK49) and outputs the selected clock signal CKp as a clock signal (reference clock signal) LTC. Therefore, the oscillation frequency Fa of the clock signal LTC (1/Ta) is basically the same as the oscillation frequency Fe (1/Ta), i.e., 100MHz, of the clock signals CK0 to CK 49. The control circuit 22 controls the DFB

semiconductor laser elements

30 and 32 so as to emit the seed lights S1 and S2 in response to each clock pulse of the clock signal LTC output from the clock switching section 204. Therefore, the oscillation frequency Fa of the pulsed light beam lba (lbb) emitted from the light source device lsa (lsb) is 100MHz in principle.

The clock switching unit 204 switches the clock signal CKp output as the clock signal LTC, that is, the clock signal CKp generated by the light beams lba (lbb), to another clock signal CKp having a different phase difference at a timing when the spot SP passes a specific correction point CPP on the scanning line. The clock switching section 204 switches the clock signal CKp selected as the clock signal LTC to the clock signal CKp ± 1 having a phase difference of 0.2nsec from the clock signal CKp currently selected as the clock signal LTC at a timing when the spot SP passes through the correction point CPP. The direction of the phase difference of the clock signals CKp ± 1, that is, the direction of the phase delay by 0.2nsec or the direction of the phase advance by 0.2nsec is determined based on 1-bit scaling information (polarity information) POL which is a part of the local magnification correction information (correction information) CMgn (CMg1 to CMg 6).

When the scaling information POL is high (1) (extended), the clock switching unit 204 selects and outputs a clock signal CKp +1, which is delayed in phase by 0.2nsec from the clock signal CKp currently output as the clock signal LTC, as the clock signal LTC. When the scaling information POL is low (reduced) by "0", the clock switching unit 204 selects and outputs a clock signal CKp-1 whose phase is advanced by 0.2nsec with respect to a clock signal CKp currently outputted as the clock signal LTC. For example, when the clock signal CKp currently output as the clock signal LTC is CK11, the clock switching unit 204 switches the clock signal CKp output as the clock signal LTC to the clock signal CK12 when the scaling information POL is high (H), and switches the clock signal CKp output as the clock signal LTC to the clock signal CK10 when the scaling information POL is low (L). The same expansion/contraction information POL is input during 1 scanning period of the spot SP.

The clock switching unit 204 determines the direction of phase shift (direction of phase advance or direction of phase delay) of the clock signal CKp output as the clock signal LTC, using the expansion/contraction information POL of the local magnification correction information CMgn corresponding to the scanning unit Un on which the light beam LBn is incident by the light beam switching unit BDU. The light beam LBa (LB1 to LB3) from the light source device LSa is guided to any one of the scanning units U1 to U3. Therefore, the clock switching unit 204 of the signal generating unit 22a of the light source device LSa determines the direction of the phase shift of the clock signal CKp output as the clock signal LTC based on the expansion/contraction information POL of the local magnification correction information CMgn corresponding to 1 scanning cell Un into which the light beam LBn is incident in the scanning cells U1 to U3. For example, when the light beam LB2 enters the scan cell U2, the clock switching unit 204 of the light source device LSa determines the direction of the phase shift of the clock signal CKp output as the clock signal LTC based on the expansion/contraction information POL of the local magnification correction information CMg2 corresponding to the scan cell U2.

The light beam LBb (LB4 to LB6) from the light source device LSb is guided to any one of the scanning units U4 to U6. Therefore, the clock switching unit 204 of the signal generating unit 22a of the light source device LSb determines the direction of the phase shift of the clock signal CKp output as the clock signal LTC based on the expansion/contraction information POL of the local magnification correction information CMgn corresponding to 1 scanning cell Un into which the light beam LBn is incident in the scanning cells U4 to U6. For example, when the light beam LB6 enters the scan cell U6, the clock switching unit 204 of the light source device LSb determines the direction of the phase shift of the clock signal CKp output as the clock signal LTC based on the expansion/contraction information POL of the local magnification correction information CMg6 corresponding to the scan cell U6.

The correction point specification unit 202 specifies a specific point on each drawing line SLn (SL1 to SL6) as a correction point CPP. The correction point specification section 202 specifies the correction point CPP based on the correction position information (set value) Nv for specifying the correction point CPP as a part of the local magnification correction information (correction information) CMgn (CMg1 to CMg 6). The correction position information Nv of the local magnification correction information CMgn is information for specifying the correction point CPP at each of a plurality of positions on the drawing line SLn which are dispersed at equal intervals in accordance with the drawing magnification of the pattern drawn along the drawing line SLn (or the drawing magnification in the main scanning direction of the drawing line SLn), and is information indicating the distance interval (equal interval) between the correction point CPP and the correction point CPP. Thus, the correction point specification unit 202 can specify the positions at which the drawing lines SLn (SL1 to SL6) are discretely arranged at equal intervals as the correction points CPP. The correction point CPP is set between the projection positions of adjacent 2 spots SP (the center positions of the spots SP) projected along the drawing line SLn, for example.

The correction point specification unit 202 specifies the correction point CPP using the correction position information Nv of the local magnification correction information CMgn corresponding to the scanning unit Un on which the light beam LBn is incident by the beam switching unit BDU. Since the light beam LBa (LB1 to LB3) from the light source apparatus LSa is guided to any one of the scanning units U1 to U3, the correction point specification section 202 specifies the correction point CPP based on the correction position information Nv of the local magnification correction information CMgn corresponding to 1 scanning unit Un into which the light beam LBn is incident in the scanning units U1 to U3. For example, when the light beam LB2 enters the scanning unit U2, the correction point specification unit 202 of the light source device LSa specifies a plurality of positions of the drawing line SLn2, which are discretely arranged at equal intervals, as the correction points CPP based on the correction position information Nv of the local magnification correction information CMg2 corresponding to the scanning unit U2.

Further, since the light beam LBb (LB4 to LB6) from the light source device LSb is guided to any one of the scanning units U4 to U6, the correction point specification section 202 of the signal generation section 22a of the light source device LSb specifies the correction point CPP based on the correction position information Nv of the local magnification correction information CMgn corresponding to 1 scanning unit Un into which the light beam LBn is incident in the scanning units U4 to U6. For example, when the light beam LB6 enters the scanning unit U6, the correction point specification unit 202 of the light source device LSb specifies a plurality of positions of the drawing line SLn6, which are discretely arranged at equal intervals, as the correction points CPP based on the correction position information Nv of the local magnification correction information CMg6 corresponding to the scanning unit U6.

Specifically describing the correction point specification unit 202, the correction point specification unit 202 includes a frequency division counter circuit 212 and a shift pulse output unit 214. The frequency division counter circuit 212 is a down counter, and is input with a clock pulse (reference clock pulse) of the clock signal LTC output from the clock switching unit 204. The clock pulse of the clock signal LTC output from the clock switching unit 204 is input to the frequency division counter circuit 212 through the gate circuit GTa. The drawing enable signals SQ1 to SQ3 indicating the drawing periods of the scan cells U1 to U3 are logical sums and applied to the gate circuit GTa. The depiction enable signals SQ1 to SQ3 are generated in response to the incident enable signals LP1 to LP3 of fig. 10. The gate circuit GTa is a gate that is opened during the period when the drawing enable signal SQn is high (H). That is, the frequency division counter circuit 212 counts the clock pulses of the clock signal LTC only during the period when the drawing permission signal SQn is high. Therefore, the gate circuit GTa of the light source device LSa outputs the clock pulse of the clock signal LTC input while any one of the drawing permission signals SQ1 to SQ3 is high (H) to the frequency division counter circuit 212. Similarly, 3 drawing enable signals SQ4 to SQ6 corresponding to the scan cells U4 to U6 are applied to the gate circuit GTa of the signal generating section 22a of the light source device LSb. Therefore, the gate circuit GTa of the light source device LSb outputs the clock pulse of the clock signal LTC input while any one of the drawing enable signals SQ4 to SQ6 is high (H) to the frequency division counter circuit 212.

The division counter circuit 212 sets an initial count value as the correction position information (set value) Nv, and decrements the count value every time a clock pulse of the clock signal LTC is input. The frequency division counter circuit 212 outputs a 1-pulse coincidence signal Idc to the shift pulse output unit 214 when the count value becomes 0. That is, the frequency division counter circuit 212 outputs the coincidence signal Idc when counting the clock pulses of the clock signal LTC by the corrected position information Nv. The coincidence signal Idc is information indicating that the correction point CPP exists before the next clock pulse is generated. When the next clock pulse is input after the count value becomes 0, the frequency division counter circuit 212 sets the count value as the correction position information Nv in advance. Thus, a plurality of correction points CPP can be specified at equal intervals along the drawing line SLn.

When the matching signal Idc is input, the shift pulse output unit 214 outputs the shift pulse CS to the clock switching unit 204. When the shift pulse CS is generated, the clock switching unit 204 switches the clock signal CKp output as the clock signal LTC. The shift pulse CS is information indicating the correction point CPP, and is generated after the count value of the frequency division counter circuit 212 becomes 0 and before the next pulse is input. Therefore, there is a correction point CPP between the position on the substrate P of the spot SP of the beam lba (lbb) generated according to the clock pulse having the count value of the frequency-division counter circuit 212 of 0 and the position on the substrate P of the spot SP of the beam lba (lbb) generated according to the next clock pulse.

When 20000 spots SP are projected for each 1 drawing line SLn as described above and 40 correction points CPP are discretely arranged at equal intervals on the drawing line SLn, the correction points CPP are arranged at intervals of 500 spots SP (clock pulses of the clock signal LTC) and the correction position information Nv is set to 500.

Fig. 12 is a timing chart showing signals output from each unit of the signal generating unit 22a shown in fig. 11. The 50 clock signals CK0 to CK49 generated by the clock signal generating unit 200 have the same reference period Te as the clock signal CK0 output from the clock generating unit 60, but have phases delayed by 0.2nsec each time. Therefore, for example, the clock signal CK3 has a phase delay of 0.6nsec with respect to the clock signal CK0, and the clock signal CK49 has a phase delay of 9.8nsec with respect to the clock signal CK 0. The frequency division counter circuit 212 outputs a matching signal Idc (not shown) when counting the clock pulses of the clock signal LTC output from the clock switching unit 204 by the corrected position information (set value) Nv, and accordingly, the shift pulse output unit 214 outputs the shift pulse CS. The shift pulse output unit 214 outputs a shift pulse CS that normally outputs a high (logic value 1) signal, but falls low (logic value 0) when the coincidence signal Idc is output, and rises high (logic value 1) when a time of half (half cycle) of the reference period Te of the clock signal CKp elapses. Thus, the shift pulse CS rises after the frequency division counter circuit 212 counts the clock pulse of the clock signal LTC by the corrected position information (set value) Nv and before the next clock pulse is input.

The clock switching unit 204 switches the clock signal CKp outputted as the clock signal LTC to the clock signal CKp ± 1 obtained by shifting the phase of the clock signal CKp outputted immediately before the shift pulse CS is generated by 0.2nsec in the direction corresponding to the scaling information POL' in response to the rise of the shift pulse CS. In the example of fig. 12, since the clock signal CKp outputted as the clock signal LTC immediately before the shift pulse CS is generated is CK0 and the scaling information POL is "0" (reduced), the shift pulse CS is switched to the clock signal CK49 in response to the rise of the shift pulse CS. In this way, when the expansion/contraction information POL is "0", the clock switching unit 204 switches the clock signal CKp output as the clock signal LTC so that the phase thereof is advanced by 0.2nsec each time the spot SP passes the correction point CPP (that is, each time the shift pulse CS is generated). Therefore, the clock signal CKp outputted (selected) as the clock signal LTC is switched in the order CK0 → CK49 → CK48 → CK47 → · · · · to. At the position of the correction point CPP generated by the shift pulse CS, the period of the clock signal LTC becomes a time (9.8nsec) shorter by 0.2nsec than the reference period Te (═ 10nsec), and thereafter, before the optical spot SP passes the next correction point CPP (before the next shift pulse CS is generated), the period of the clock signal LTC becomes the reference period Te (═ 10 nsec).

On the contrary, when the expansion/contraction information POL is "1", the clock switching unit 204 switches the clock signal CKp outputted (selected) as the clock signal LTC so that the phase thereof is delayed by 0.2nsec each time the light spot SP passes the correction point CPP (that is, each time the shift pulse CS is generated). Therefore, the clock signal CKp outputted (selected) as the clock signal LTC is switched in the order CK0 → CK1 → CK2 → CK3 → · · · · to. At the position of the correction point CPP generated by the shift pulse CS, the period of the clock signal LTC becomes a time (10.2nsec) longer by 0.2nsec than the reference period Te (═ 10nsec), and thereafter, before the optical spot SP passes the next correction point CPP (before the next shift pulse CS is generated), the period of the clock signal LTC becomes the reference period Te (═ 10 nsec).

In the present embodiment, since the spot SP having an effective size of 3 μm is projected in the main scanning direction so as to overlap 1.5 μm each time, the correction time (± 0.2nsec) of the period of the clock signal LTC at the correction point CPP corresponds to 0.03 μm (± 1.5 [ μm ] × (± 0.2 [ nsec ]/10 [ nsec ])), and ± 0.03 μm per 1 pixel expansion and contraction.

Fig. 13A is a diagram illustrating the pattern PP drawn when the local magnification correction is not performed, and fig. 13B is a diagram illustrating the pattern PP drawn when the local magnification correction (reduction) is performed according to the timing chart shown in fig. 12. Further, the spot SP with high intensity is shown by a solid line, and the spot SP with low or zero intensity is shown by a broken line. As shown in fig. 13A and 13B, a pattern PP is drawn by the spot SP generated in response to each clock pulse of the clock signal LTC. In order to distinguish the clock signal LTC from the pattern PP in fig. 13A and 13B, the clock signal LTC and the pattern PP in fig. 13A (when the local magnification correction is not performed) are represented by LTC1 and PP1, and the clock signal LTC and the pattern PP in fig. 13B (when the local magnification correction is performed) are represented by LTC2 and PP 2.

When the partial magnification correction is not performed, as shown in fig. 13A, the size Pxy of each pixel drawn is a fixed length in the main scanning direction. The length of the pixel in the sub-scanning direction (X direction) is denoted by Px, and the length in the main scanning direction (Y direction) is denoted by Py. When the partial magnification correction (reduction) is performed according to the timing chart shown in fig. 12, as shown in fig. 13B, the size Pxy of the pixel including the correction point CPP is in a state where the length Py of the pixel is reduced by Δ Py (═ 0.03 μm). Conversely, when the local magnification correction of the extension is performed, the size Pxy of the pixel including the correction point CPP is in a state where the length Py of the pixel is extended by Δ Py (═ 0.03 μm).

Further, although not particularly mentioned, the pixel shift of the serial data DLn is performed by shifting the logic information of the pixels of the serial data DLn outputted to the driving circuit 36a of the light source device lsa (lsb) by 1 pixel (1 bit) by the drawing data output unit 114 shown in fig. 9 every time 2 clock pulses of the clock signal LTC are outputted from the clock switching unit 204. Thus, 2 spots SP (clock pulses of the clock signal LTC) correspond to 1 pixel.

As described above, the exposure apparatus EX of the present embodiment draws a pattern on the substrate P by modulating the intensity of the spot SP of the light beam LB (Lse, LBa, LBb, LBn) generated from the seed lights S1, S2 from the pulse light source unit 35 based on pattern data and relatively scanning the spot SP along the drawing line SLn on the substrate P. The exposure apparatus EX includes at least a clock signal generating section 200, a control circuit (light source control section) 22, and a clock switching section 204. As described above, the clock signal generating unit 200 generates a plurality of (N ═ 50) clock signals CKp (CK0 to CK49) having a reference period Te (for example, 10nsec) shorter than the period determined by Φ/Vs and giving a phase difference in units of a correction time (for example, 0.2nsec) of 1/N of the reference period Te. The control circuit (light source control section) 22 controls the pulse light source section 35 to generate the light beam LB in response to each clock pulse of any one clock signal CKp (clock signal LTC) of the plurality of clock signals CKp. The clock switching unit 204 switches the clock signal CKp caused by the generation of the light beam LB, i.e., the clock signal CKp output as the clock signal LTC, to other clock signals CKp having different phase differences at a timing when the spot SP passes a specific correction point CPP specified on the trace line SLn. Therefore, the magnification of the drawing line SLn (drawn pattern) can be finely corrected, and precise overlay exposure on the order of micrometers can be performed.

The correction position information (set value) Nv of the local magnification correction information CMgn (CMg1 to CMg6) can be arbitrarily changed and is appropriately set in accordance with the magnification of the drawing line SLn. For example, the corrected position information Nv may be set so that the number of correction points CPP located on the drawing line SLn is 1. The value of the corrected position information Nv may be changed every 1 scan of the spot SP along the scanning line SLn, or may be changed every 1 scan when the spot SP is located at the corrected point CPP. In this case, although the plurality of correction points CPP are specified at discrete positions on the drawing line SLn, the intervals between the correction points CPP may be made non-uniform by changing the correction position information Nv. Further, the position of the correction pixel (correction point CPP) may be made different by changing the number of correction pixels on the drawing line SLn every 1 scan of the light flux LBn (light spot SP) along the drawing line SLn or every 1 rotation of the polygon mirror PM.

[ modification of embodiment 1 ]

The above embodiment 1 can be modified as follows. The same components as those in the above embodiment are denoted by the same reference numerals, and different portions will be mainly described.

(modification 1)

In the above embodiment 1, the selection optical elements AOMn (AOM1 to AOM6) for selectively supplying the light beam lba (lbb) from the light source device lsa (lsb) to any one of the scanning units Un (U1 to U6) are acousto-optic modulators. That is, although 1 st-order diffracted light, which is deflected at a specific diffraction angle with respect to an incident light beam and is output, is supplied to the scanning unit Un as the light beam LBn for drawing, the selective optical elements AOMn (AOM1 to AOM6) may be photoelectric deflection members that do not use diffraction phenomenon. Fig. 14 shows a configuration of a beam switching unit corresponding to 1 scanning unit Un in the beam switching unit BDU of modification 1, and in this modification, a photoelectric element OSn that allows the light beam lba (lbb) from the light source device lsa (lsb) to enter and a polarization beam splitter BSn that transmits or reflects the light beam according to the polarization characteristics of the light beam transmitted through the photoelectric element OSn are provided instead of the combination system of the optical element AOM1 for selection and the unit-side entrance mirror IM1 shown in fig. 6.

In fig. 14, when the light beam lba (lbb) incident on the photoelectric element OSn is linearly polarized in the Y direction when the traveling direction of the light beam lba (lbb) emitted as a parallel light beam from the light source device lsa (lsb) is set to be parallel to the X axis, and when a voltage of several Kv is applied between the electrodes EJp, EJm formed on the surface of the photoelectric element OSn facing in the Y direction, the light beam having passed through the photoelectric element OSn becomes linearly polarized in the Z direction after being rotated by 90 degrees from the polarization state at the time of incidence, and is incident on the polarization beam splitter BSn. When no voltage is applied between the electrodes EJp and EJm, the light beam having passed through the photoelectric element OSn becomes linearly polarized light polarized in the Y direction while maintaining the polarization state at the time of incidence. Therefore, in the off state where the voltage between the electrodes EJp and EJm is zero, the light beam from the photoelectric element OSn directly transmits the polarization splitting plane psp (a plane inclined at 45 degrees to each of the XY plane and the YZ plane) of the cube-shaped polarization beam splitter BSn. In the on state where a voltage is applied between the electrodes EJp and EJm, the light beam from the photoelectric element OSn is reflected on the polarization splitting plane psp of the polarization beam splitter BSn, becomes a drawing light beam LBn intensity-modulated in accordance with drawing data (for example, drawing bit string data SBa and SBb in fig. 9), and is directed to the scanning unit Un. The photoelectric element OSn is composed of a crystalline medium or an amorphous medium exhibiting a peck effect in which the refractive index changes to the 1 st power of the applied electric field intensity or a peck effect in which the refractive index changes to the 2 nd power of the applied electric field intensity. The photoelectric element OSn may be a crystal medium exhibiting a faraday effect in which the refractive index is changed by a magnetic field instead of an electric field.

(modification 2)

Fig. 15 shows modification 2 in the case where the optical elements AOM1 to AOM6 for selection and the cell-side incident mirrors IM1 to IM6 constituting the beam switching portion BDU shown in fig. 6 are replaced with the configuration of modification 1 shown in fig. 14. A linearly polarized light beam LBa emitted as a parallel light beam (having a beam diameter of 1mm or less) from the light source device LSa passes through a beam shifter unit SFTa using an acousto-optic modulator (or an acousto-optic deflecting element) shown in fig. 6 and 9, passes through the photoelectric element OS1, the polarization beam splitter BS1, the photoelectric element OS2, the polarization beam splitter BS2, the photoelectric element OS3, and the polarization beam splitter BS3 in this order, and then enters the absorber TR 1. When an electric field is applied to the photoelectric element OS1, the polarization beam splitter BS1 reflects the light beam LBa as a drawing light beam LB1 toward the scanning unit U1. Similarly, the polarization beam splitter BS2 reflects the light beam LBa as the drawing light beam LB2 toward the scanning unit U2 when the electric field is applied to the photoelectric element OS2, and the polarization beam splitter BS3 reflects the light beam LBa as the drawing light beam LB3 toward the scanning unit U3 when the electric field is applied to the photoelectric element OS 3. In fig. 15, an electric field is applied only to the photoelectric element OS2 among the photoelectric elements OS1 to OS3, and the light beam LBa emitted from the beam phase shifter portion SFTa is incident only on the scanning unit U2 as the light beam LB 2.

Similarly, a linearly polarized light beam LBb emitted as a parallel light beam (having a beam diameter of 1mm or less) from the light source device LSb is made incident on the absorber TR2 after passing through the beam shifter portion SFTb using the acoustic-optical modulator (or the acoustic-optical deflecting element) and passing through the photoelectric element OS4, the polarization beam splitter BS4, the photoelectric element OS5, the polarization beam splitter BS5, the photoelectric element OS6, and the polarization beam splitter BS6 in this order. The polarization beam splitter BS4 reflects the light beam LBb as the light beam LB4 for drawing toward the scanning unit U4 when the electric field is applied to the photoelectric element OS4, the polarization beam splitter BS5 reflects the light beam LBb as the light beam LB5 for drawing toward the scanning unit U5 when the electric field is applied to the photoelectric element OS5, and the polarization beam splitter BS6 reflects the light beam LBb as the light beam LB6 for drawing toward the scanning unit U6 when the electric field is applied to the photoelectric element OS 6. In fig. 15, an electric field is applied only to the photoelectric element OS6 among the photoelectric elements OS4 to OS6, and the light beam LBb emitted from the beam phase shifter portion SFTb is incident only on the scanning unit U6 as the light beam LB 6.

For example, the beam phase shifter portions SFTa and SFTb are configured as shown in fig. 16 using the acousto-optic deflection elements AODs. The acousto-optic deflection elements AODs are driven by high-frequency drive signals HGa and HGb which are the same as the drive signal HFn as the high-frequency power from the selection element drive control section 102 shown in fig. 9. The parallel light fluxes lba (lbb) from the light source units lsa (lsb) enter coaxially with the optical axis of the lens CG1 having the focal length f1, and are condensed on the surface pu so as to form a beam waist. The deflection point of the acousto-optic deflection elements AODs is arranged at the position of the plane pu. In a state where the drive signals hga (hgb) are off, the light beam lba (lbb) having the beam waist on the surface pu enters the lens CG2 with the focal length f2 without being diffracted, and is reflected by the mirror OM after becoming a parallel beam and enters the absorber TR 3. In an on state where the drive signal hga (hgb) is applied to the acousto-optic deflection element AODs, the acousto-optic deflection element AODs generates 1-time diffracted light of the beam lba (lbb) deflected at a diffraction angle corresponding to the frequency of the drive signal hga (hgb). Here, the 1-time diffracted light is referred to as a deflected light beam lba (lbb). Since the deflection point of the acousto-optic deflection element AODs is disposed on the plane pu which is the position of the focal length f2 of the lens CG2, the light beam lba (lbb) emitted from the lens CG2 becomes a parallel light beam parallel to the optical axis of the lens CG2, and enters the photoelectric element OS1 or OS4 of fig. 15.

By changing the frequency of the drive signals hga (hgb) applied to the acousto-optic deflection elements AODs, the light beams lba (lbb) emitted from the lens CG2 are displaced in the direction perpendicular to the optical axis in a state parallel to the optical axis of the lens CG 2. The direction of the positional displacement of light beam lba (lbb) corresponds to the Z direction on the incident end surface of photoelectric element OSn (OS1 or OS4) shown in fig. 14, and the amount of the displacement corresponds to the amount of change in the frequency of drive signal hga (hgb). In the case of the present modification, the beam phase shifter portion sfta (sftb) is provided in common to the 3 scanning units U1, U2, and U3(U4, U5, and U6). Therefore, the frequency of the drive signal hga (hgb) applied to the acousto-optic deflection elements AODs can be changed (frequency modulation) in synchronization with the timing at which any one of the photoelectric elements OS1 to OS3 or any one of the photoelectric elements OS4 to OS6 in fig. 15 is turned on. Thus, the light beams lba and lbb passing through the photoelectric elements OS1 to OS3(OS4 to OS6) are shifted in parallel to the Z direction in fig. 14, and the light beams LBn (LB1 to LB6) reflected by the polarization beam splitters BS1 to BS3(BS4 to BS6) are shifted in parallel to the X direction in fig. 14. Thereby, the spot SP of the light beam LBn from the scanning unit Un corresponding to the photoelectric element OSn that has been turned on can be quickly shifted by a small amount in the sub-scanning direction (X direction).

As described above, in the present embodiment, since the photoelectric elements OS1 to OS3(OS4 to OS6) having no deflection function are used to selectively distribute the light beam lba (lbb) from the light source device lsa (lsb) to any one of the 3 scanning units U1 to U3(U4 to U6), the beam phase shifter portion sfta (sftb) using the acousto-optic deflection element AODs having a deflection function is provided to finely adjust the position of the light spot SP in the sub-scanning direction.

(modification 3)

Fig. 17A and B show an example of a beam deflecting member which is provided instead of the optical elements for selection AOMs 1 to AOM6 or the acousto-optic deflecting elements AODs used in the above-described embodiments or modifications and which does not use diffraction action. Fig. 17A shows a photoelectric element ODn in which electrodes EJp and EJm are formed on opposing parallel side surfaces (upper and lower surfaces in fig. 17A) of a transparent crystalline medium formed in a prism shape (triangle shape) with a specific thickness. The crystalline medium is a material represented by KDP (KH2PO4), ADP (NH4H2PO4), KD x P (KD2PO4), KDA (KH2AsO4), BaTiO3, SrTiO3, LiNbO3, LiTaO3, or the like as a chemical composition. The light beam lba (lbb) incident from one inclined plane of the photoelectric element ODn is deflected according to the difference between the initial refractive index of the crystal medium and the refractive index of air when the electric field between the electrodes EJp, EJm is zero, and exits from the other inclined plane. When an electric field of a fixed value or more is applied between the electrodes EJp, EJm, the refractive index of the crystal medium changes from the initial value, and thus the incident light beam lba (lbb) becomes a light beam LBn emitted from another inclined plane at an angle different from the initial angle. Even if such a photoelectric element ODn is used, the light beams lba (lbb) from the light source devices lsa (lsb) can be switched and supplied to each of the scanning units U1 to U6 in a time-division manner. Further, since the deflection angle of the emitted light beam LBn can be changed slightly and quickly by changing the intensity of the electric field applied to the photoelectric element ODn, the photoelectric element ODn can be provided with both a switching function and a light beam shifting function for shifting the light spot SP on the substrate P slightly in the sub-scanning direction. Further, the photoelectric element ODn may be used instead of the acousto-optic deflection elements AODs of the individual beam phase shifter portions sfta (sftb) as shown in fig. 16.

Further, fig. 17B shows an example of a beam deflecting member using a photoelectric element KDn using a KTN (KTa1-xNbxO3) crystal as disclosed in, for example, japanese patent laid-open publication No. 2014-081575 and international publication No. 2005/124398. In fig. 17B, the photoelectric element KDn is composed of a crystal medium formed in a long angular pillar shape along the traveling direction of the light beam lba (lbb), and electrodes EJp, EJm arranged to face each other with the crystal medium interposed therebetween. The photoelectric element KDn is housed in a case having a temperature adjustment function so as to be kept at a constant temperature (for example, about 40 degrees). When the electric field intensity between the electrodes EJp, EJm is zero, the light beam lba (lbb) incident from one end face of the prism-shaped KTN crystal medium linearly advances in the KTN crystal medium and is emitted from the other end face. When an electric field strength is applied between the electrodes EJp, EJm, the light beam lba (lbb) in the KTN crystal medium is deflected in the direction of the electric field and is emitted from the other end face as a light beam LBn. The KTN crystal medium is also a material whose refractive index varies depending on the electric field intensity, but a large variation in refractive index is obtained at an electric field intensity lower by one bit (several hundred V) as compared with the various crystal media listed above. Therefore, by changing the voltage applied between the electrodes EJp and EJm, the deflection angle of the light beam LBn emitted from the photoelectric element KDn with respect to the original light beam lba (lbb) can be quickly adjusted within a relatively wide range (for example, 0 degree to 5 degrees).

Even if such a photoelectric element KDn is used, the light beams lba (lbb) from the light source devices lsa (lsb) can be switched and supplied to each of the scanning units U1 to U6 in a time-sharing manner. Further, since the deflection angle of the emitted light beam LBn can be changed rapidly by changing the intensity of the electric field applied to the photoelectric element KDn, the photoelectric element KDn can have both a switching function and a function of shifting the spot SP on the substrate P in the sub-scanning direction. Further, the photoelectric element KDn may be used instead of the acousto-optic deflection elements AODs of the individual beam phase shifter portions sfta (sftb) shown in fig. 16.

According to the above embodiment 1 and its modifications, in order to shift the light spot SP of each scan along the scanning line SLn in the sub-scanning direction, there are provided a mechanical-optical phase shifter using the shift optical member SR (parallel flat plate SR2) provided in each of the scanning units Un (U1 to U6), and a photoelectric phase shifter shifting the light beam LBn incident on each of the scanning units Un (U1 to U6) using the acousto-optical deflecting elements AODs, the photoelectric elements OSn, ODn, KDn, and the like. Therefore, when the positional relationship in the sub-scanning direction of the drawing line SLn based on the scanning of the spot SP of the light beam LBn from each of the scanning units Un (U1 to U6) is corrected (calibrated) to a specific state (initial arrangement state, etc.), the amount of error remaining even by the correction is corrected more finely by the photo-electric phase shifters (acousto-optical deflection elements AODs, photo-electric elements OSn, ODn, KDn) using the mechanical-optical phase shifter (parallel flat plate Sr 2).

[ embodiment 2 ]

Next, embodiment 2 will be explained. The same components as those in the above-described embodiments (including the modifications) are denoted by the same reference numerals, and only different portions will be described. In the configuration of fig. 6 described as the above embodiment, a plurality of beam waists (focal points) are formed for the light beams lba (lbb) from the light source unit lsa (lsb) by a plurality of relay systems based on the condenser lens CD and the collimator lens (collimator lens) LC, and the optical elements for selection (acousto-optic modulators) AOM1 to AOM6 are disposed at the positions of the beam waists. Since the beam waist position of the beam lba (lbb) is set so as to be optically conjugate with the surface of the substrate P (each of the light spots SP of the beams LB1 to LB6) finally, even if an error occurs in the deflection angle due to a characteristic change or the like of the optical elements (acousto-optic modulators) AOMs 1 to AOM6 for selection, a shift of the light spot SP on the substrate P in the sub-scanning direction (Xt direction) can be suppressed. Therefore, when the drawing line SLn of the light spot SP is finely adjusted in the sub-scanning direction (Xt direction) in a range of about the pixel size (several μm) for each scanning unit Un, the parallel flat plate Sr2 in the scanning unit Un shown in fig. 5 may be inclined. Further, in order to automate the tilting of the parallel flat plate Sr2, a mechanism such as a small piezoelectric motor or a monitor system of a tilting amount may be provided.

However, even if the inclination of the parallel flat plate Sr2 is automated, since it is mechanically driven, it is difficult to control with high responsiveness corresponding to the time of 1 rotation amount of the polygon mirror PM, for example. Therefore, in embodiment 2, the optical configuration or arrangement of the beam delivery system (beam switching unit BDU) from the light source device LS (LSa, LSb) to each scanning unit Un as shown in fig. 7 is slightly changed, and the optical elements for selection (acousto-optic modulators) AOM1 to AOM6 have both a beam switching function and a shift function of finely adjusting the position of the spot SP in the sub-scanning direction. The structure of embodiment 2 will be described below with reference to fig. 18 to 22.

Fig. 18 is a diagram showing in detail the structure of the wavelength converter in the pulse light generator 20 of the light source device lsa (lsb) shown in fig. 7, fig. 19 is a diagram showing the optical path of the light beam LBa (LBb omitted) from the light source device lsa (lsb) to the first selective optical element AOM1, fig. 20 is a diagram showing the structure of the optical path from the selective optical element AOM1 to the next-stage selective optical element AOM2 and the drive circuit of the selective optical element AOM1, fig. 21 is a diagram showing the case of beam selection and beam shift in the selective mirror (branching mirror) IM1 after the selective optical element AOM1, and fig. 22 is a diagram showing the operation of the light beam from the polygon mirror PM to the substrate P.

As shown in fig. 18, the amplified seed light (light beam) Lse is emitted from an emission end 46a of the fiber optical amplifier 46 in the light source device LSa at a small divergence angle (NA: numerical aperture). The lens element gl (gla) condenses the seed light Lse so as to form a beam waist in the 1 st wavelength conversion element (wavelength conversion optical element) 48. Therefore, the 1 st harmonic light flux subjected to the wavelength conversion by the 1 st wavelength conversion element 48 is divergently incident on the lens element gl (glb). The lens element GLb condenses the 1 st harmonic beam so as to form a beam waist in the 2 nd wavelength conversion element (wavelength conversion optical element) 50. The 2 nd harmonic light beam wavelength-converted by the 2 nd wavelength conversion element 50 is divergently incident on the lens element gl (glc). The lens element GLc is disposed so that the 2 nd harmonic light flux becomes substantially parallel beamlets lba (lbb) and is emitted from the emission window 20H of the light source device LSa. The diameter of the light beam LBa emitted from the emission window 20H is several mm or less, preferably about 1 mm. In this way, each of the

wavelength conversion elements

48 and 50 is set so as to be optically conjugate with the emission end 46a (light emission point) of the fiber optical amplifier 46 by the lens elements GLa and GLb. Therefore, even when the traveling direction of the generated harmonic light beam is slightly inclined due to the variation in the crystal characteristics of the

wavelength conversion elements

48 and 50, the shift in the angular direction (azimuth) of the light beam LBa emitted from the emission window 20H can be suppressed. In fig. 18, the lens element GLc is shown separately from the emission window 20H, but the lens element GLc itself may be disposed at the position of the emission window 20H.

As shown in fig. 19, the light flux LBa emitted from the emission window 20H travels along the optical axis AXj of the expander system including 2 condenser lenses CD0 and CD1, is converted into a substantially parallel light flux whose beam diameter is reduced to about 1/2 (about 0.5 mm), and is incident on the 1 st-stage optical element AOM 1. The light flux LBa from the exit window 20H becomes a beam waist at a condensing position Pep between the condenser lens CD0 and the condenser lens CD 1. The condenser lens CD1 is provided as the condenser lens CD1 in fig. 6 described above. Further, the deflection position Pdf (diffraction point) of the light beam in the selective optical element AOM1 is set so as to be optically conjugate with the exit window 20H by an expander system based on the condenser lenses CD0 and CD 1. Further, the light converging position Pep is set so as to be optically conjugate with the emission end 46a of the optical fiber optical amplifier 46 and the

wavelength conversion elements

48 and 50 in fig. 18. The direction of deflection of the light beam by the selective optical element AOM1, that is, the diffraction direction of the light beam LB1 emitted as 1-time diffracted light of the incident light beam LBa, is set to the Z direction (the direction in which the spot SP on the substrate P is shifted in the sub-scanning direction). The beam LBa of the selective optical element AOM1 becomes, for example, a parallel beam having a beam diameter of about 0.5mm, and the beam LB1 emitted as 1-time diffracted light also becomes a parallel beam having a beam diameter of about 0.5 mm. That is, in each of the above embodiments (including the modifications), the beam lba (lbb) is converged to be a beam waist in the selective optical element AOM1, but in the present embodiment 2, the beam lba (lbb) passing through the selective optical element AOM1 is a parallel beam having a minute diameter.

As shown in fig. 20, both the light beam LBa transmitted through the selective optical element AOM1 and the light beam LB1 deflected as 1-time diffraction at the time of switching are incident on a collimator lens CL1 (corresponding to the lens CL1 in fig. 6) arranged coaxially with the optical axis AXj. The deflection position Pdf of the optical element for selection AOM1 is set to the position of the front focus of the collimator lens CL 1. Therefore, the light flux LBa and the light flux LB1 converge to beam waists on the rear focal surface Pip of the collimator lens (condenser lens) CL 1. The light beam LBa proceeding along the optical axis AXj of the collimator lens CL1 enters the condenser lens (condenser lens) CD2 shown in fig. 6 in a divergent state from the plane Pip, becomes a parallel light beam having a beam diameter of about 0.5mm again, and enters the 2 nd stage selection optical element AOM 2. The deflection position Pdf of the 2 nd stage selection optical element AOM2 is arranged in a conjugate relationship with the deflection position Pdf of the selection optical element AOM1 by a relay system based on the collimator lens CL1 and the condenser lens CD 2.

The selecting mirror IM1 shown in fig. 6 is disposed in the vicinity of the plane Pip between the collimator lens CL1 and the condenser lens CD2 in embodiment 2. Since the beams LBa and LB1 are the finest beam waists at the surface Pip and are separated in the Z direction, the arrangement of the reflection surface IM1a of the mirror IM1 is facilitated. The deflection position Pdf and the plane Pip of the optical element AOM1 for selection are in the relationship between the pupil position and the image plane by the collimator lens CL1, and the central axis (principal ray) of the light beam LB1 directed from the collimator lens CL1 toward the reflection surface IM1a of the mirror IM1 becomes parallel to the principal ray (optical axis AXj) of the light beam LBa. The light beam LB1 reflected on the reflecting surface IM1a of the mirror IM1 is converted into a parallel light beam by a collimator lens CL1a equivalent to the condenser lens CD2, and directed to the mirror M10 of the scanning unit U1 shown in fig. 5. The plane Pip is optically conjugate with the condensing position Pep by the collimator lens CL1 and the condenser lens CD1 in fig. 19. Therefore, the plane Pip is also in conjugate relation with the emission end 46a of the fiber optical amplifier 46 and the

wavelength conversion elements

48 and 50 in fig. 18. That is, the plane Pip is set so as to be conjugate with the output end 46a of the fiber optical amplifier 46 and the

wavelength conversion elements

48 and 50, respectively, by the relay lens system constituted by the lens elements GLa, GLb, GLc, the condenser lenses CD0, CD1, and the collimator lens CL 1.

The optical axis AXm of the collimator lens CL1a is set to be coaxial with the irradiation center line Le1 in fig. 5, and when the deflection angle of the light beam LB1 by the selection optical element AOM1 at the time of switching is a predetermined angle (a reference setting angle), the center line (principal ray) of the light beam LB1 enters the collimator lens CL1a so as to be coaxial with the optical axis AXm. As shown in fig. 20, the reflecting surface IM1a of the mirror IM1 is set to a size that reflects only the light beam LB1 so as not to interrupt the optical path of the light beam LBa, and that reliably reflects the light beam LB1 even when the light beam LB1 reaching the reflecting surface IM1a is slightly displaced in the Z direction. However, when the reflecting surface IM1a of the mirror IM1 is arranged at the position of the plane Pip, a spot on which the light beam LB1 is condensed is formed on the reflecting surface IM1a, and therefore, it is preferable that the mirror IM1 is arranged so as to be shifted in the X direction so that the reflecting surface IM1a is slightly shifted from the position of the plane Pip. Further, a reflective film (dielectric multilayer film) having high ultraviolet resistance is formed on the reflective surface IM1 a.

In embodiment 2, a drive circuit 102A for providing both the switching function and the shifting function of the light beam to the selection optical element AOM1 is provided in the selection element drive control unit 102 shown in fig. 9. The drive circuit 102A is constituted by: a local oscillation circuit 102A1 (VCO: voltage controlled oscillator, etc.) that receives a correction signal FSS for changing the frequency of the drive signal HF1 applied to the selective optical element AOM1 from a reference frequency and generates a corrected high frequency signal corresponding to the frequency to be corrected; a hybrid circuit 102a2 that synthesizes a high-frequency signal having a stable frequency generated by the reference oscillator 102S and a corrected high-frequency signal from the local oscillator circuit 102a1 by adding and subtracting the frequencies; and an amplifier circuit 102A3 that converts the high-frequency signal frequency-synthesized by the hybrid circuit 102a2 into a drive signal HF1 amplified to an amplitude suitable for driving the ultrasonic transducer of the optical element AOM 1. The amplifier circuit 102a3 has a switching function of switching the high-frequency drive signal HF1 between a high level and a low level (or amplitude zero) in response to the incident permission signal LP1 generated in the selection device drive control unit 102 in fig. 9. Therefore, during a period when the drive signal HF1 has a high amplitude (during a period when the signal LP1 has an H level), the optical element AOM1 is selected to deflect the beam LBa and generate the beam LB 1. The optical system and the drive circuit 102A of the mirror IM1 and the collimator lens CL1a as shown in fig. 20 are provided similarly for the other optical elements AOM2 to AOM 6. In the above configuration, the local oscillation circuit 102a1 and the hybrid circuit 102a2 function as a frequency modulation circuit that changes the frequency of the drive signal HF1 in accordance with the value of the correction signal FSS.

In the drive circuit 102A, when the correction signal FSS indicates that the correction amount is zero, the frequency of the drive signal HF1 output from the amplifier circuit 102A3 is set to a predetermined frequency such that the deflection angle of the beam LB1 based on the optical element for selection AOM1 becomes a predetermined angle (reference set angle). When the correction signal FSS indicates the correction amount + Δ Fs, the frequency of the drive signal HF1 is corrected so that the deflection angle of the beam LB1 based on the selective optical element AOM1 is increased by Δ θ γ with respect to a predetermined angle. When the correction signal FSS indicates the correction amount — Δ Fs, the frequency of the drive signal HF1 is corrected so that the deflection angle of the beam LB1 based on the selective optical element AOM1 is decreased by Δ θ γ from a predetermined angle. When the deflection angle of the light beam LB1 changes ± Δ θ γ from the predetermined angle, the position of the light beam LB1 incident on the reflection surface IM1a of the mirror IM1 is slightly shifted in the Z direction, and the light beam LB1 (parallel light beam) emitted from the collimator lens CL1a is slightly inclined with respect to the optical axis AXm. This will be further described with reference to fig. 21.

Fig. 21 is an enlarged optical path diagram showing a state of displacement of the light beam LB1 deflected by the selective optical element AOM 1. When the light beam LB1 is deflected at a predetermined angle by the selective optical element AOM1, the central axis of the light beam LB1 is coaxial with the optical axis AXm of the collimator lens CL1 a. At this time, the center axis of the light beam LB1 emitted from the autocollimator lens CL1 is separated from the center axis of the original light beam LBa (optical axis AXj) by Δ SF0 in the-Z direction. When the frequency of the drive signal HF1 for driving the selective optical element AOM1 is increased by Δ Fs, for example, from this state, the deflection angle of the beam LB1 at the selective optical element AOM1 is increased by Δ θ γ from the predetermined angle, and the center axis AXm 'of the beam LB 1' reaching the mirror IM1 is positioned away from the optical axis AXj by Δ SF1 in the-Z direction. In this way, the central axis AXm 'of the light beam LB 1' directed to the mirror IM1 is laterally displaced (parallel-moved) in the-Z direction by Δ SF1 to Δ SF0 from a predetermined position (a position coaxial with the optical axis AXm) in accordance with a change in Δ Fs of the frequency of the drive signal HF 1.

On the optical axis AXm, there is a plane Pip 'corresponding to the plane Pip where the beam LB1(LB 1') is converged to form a beam waist. The central axis AXm ' of the light beam LB1 ' directed from the plane Pip ' toward the collimator lens CL1a is parallel to the optical axis AXm, and the light beam LB1 ' emitted from the collimator lens CL1a is converted into a parallel light beam slightly inclined in the XZ plane with respect to the optical axis AXm by setting the plane Pip ' at the position of the front focal point of the collimator lens CL1 a. In the present embodiment, the lens systems (the lenses Be1, Be2, the cylindrical lenses CYa, CYb, and f θ lens TF in fig. 5) in the scanning unit U1 are arranged so that the plane Pip' is finally conjugate with the surface of the substrate P (the spot SP).

Fig. 22 is a view obtained by spreading the optical path from the 1 reflection surface rp (rpa) of the polygon mirror PM in the scanning unit U1 to the substrate P and observing the optical path from the Yt direction. The beam LB1 deflected at a predetermined angle by the selective optical element AOM1 is incident on the reflection surface RPa of the polygon mirror PM in a plane parallel to the XtYt plane and is reflected. The light beam LB1 incident on the reflection surface RPa is converged in the Zt direction on the reflection surface RPa by the 1 st cylindrical lens CYa shown in fig. 5 in the XtZt plane. The light flux LB1 reflected on the reflection surface RPa is deflected at a high speed in accordance with the rotation speed of the polygon mirror PM in a plane parallel to the XtYt plane including the optical axis AXf of the f θ lens FT, and is condensed as the spot SP on the substrate P via the f θ lens FT and the 2 nd cylindrical lens CYb. The spot SP is scanned one-dimensionally in a direction perpendicular to the paper surface in fig. 21.

On the other hand, as shown in fig. 21, the light beam LB1 'that has been shifted laterally in the plane Pip' by Δ SF1 to Δ SF0 with respect to the light beam LB1 is incident on a position slightly shifted in the Zt direction with respect to the irradiation position of the light beam LB on the reflection surface RPa of the polygon mirror PM. Accordingly, the optical path of the light beam LB1 'reflected by the reflection surface RPa is slightly shifted from the optical path of the light beam LB1 in the XtZt plane, passes through the f θ lens FT and the 2 nd cylindrical lens CYb, and is focused on the substrate P as the spot SP'. The reflection surface RPa of the polygon mirror PM is optically arranged on the pupil plane of the f θ lens FT, and the reflection surface RPa and the surface of the substrate P are in a conjugate relationship in the XtZt plane of fig. 22 due to the effect of the surface tilt correction of the 2 cylindrical lenses CYa and CYb. Therefore, when the light beam LB1 irradiated onto the reflection surface RPa of the polygon mirror PM is slightly shifted in the Zt direction like the light beam LB1 ', the light spot SP on the substrate P is shifted by Δ SFp in the sub-scanning direction like the light spot SP'.

As in the above configuration, the frequency of the drive signal HF1 of the selection optical element AOM1 is changed from the predetermined frequency by ± Δ Fs, whereby the spot SP can be shifted by ± Δ SFp in the sub-scanning direction. The shift amount (| Δ SFp |) is limited by the maximum range of the deflection angle of the optical element AOM1 itself for selection, the size of the reflection surface IM1a of the mirror IM1, the magnification of the optical system (relay system) to the polygon mirror PM in the scanning unit U1, the width of the reflection surface of the polygon mirror PM in the Zt direction, the magnification from the polygon mirror PM to the substrate P (the magnification of the f θ lens FT), and the like, but is set to a range of an effective size (diameter) on the substrate P of the spot SP or a pixel size (Pxy) defined on the drawing data. Of course, the shift amount may be set to be larger than this. The selective optical element AOM1 and the scanning unit U1 are described, but the same applies to the other selective optical elements AOM2 to AOM6 and the scanning units U2 to U6.

As described above, in the present embodiment, the optical elements for selection AOMn (AOM1 to AOM6) can be used in combination for the beam switching function in response to the incident permission signals LPn (LP1 to LP6) and the displacement function of the spot SP in response to the correction signal FSS, and therefore, the configuration of the beam delivery system (beam switching unit BDU) for supplying the beam to each scanning unit Un (U1 to U6) is simplified. Further, compared with the case where an acousto-optic modulator (AOM or AOD) for beam selection and displacement of the spot SP is provided for each scanning unit Un, the heat generation source can be reduced, and the temperature stability of the exposure apparatus EX can be improved. In particular, the drive circuit (102A) for driving the acousto-optic modulator becomes a large heat source, and the drive signal HF1 is a high frequency of 50MHz or more, and is therefore disposed in the vicinity of the acousto-optic modulator. Even if a mechanism for cooling the drive circuit (102A) is provided, if the number of the mechanisms is large, the temperature in the device is easy to rise in a short time, and the drawing accuracy may be reduced due to the fluctuation caused by the temperature change of the optical system (lens or mirror). Therefore, it is preferable that the number of driver circuits and acoustic optical modulators to be heat sources is small. In the case where the deflection angle of the light beam LBn deflected by 1-time diffracted light as the incident light beam lba (lbb) is varied by the respective optical elements AOMn (AOM1 to AOM6) under the influence of temperature change, in the present embodiment, the variation in the deflection angle can be easily canceled out by providing a feedback control system that adjusts the value of the correction signal FSS applied to the drive circuit 102A of fig. 20 in accordance with the temperature change.

The beam shift function of the optical element AOMn for selection according to the present embodiment can finely adjust the position of the drawing line SLn of the spot SPn of the beam LBn from each of the plurality of scanning units Un in the sub-scanning direction at a high speed. For example, if the optical element for selection AOM1 shown in fig. 20 is controlled so that the correction amount based on the correction signal FSS is changed every time the incident permission signal LP1 becomes the H level, the scanning line SL1 can be shifted in the sub-scanning direction by a range of the pixel size (or the size of the light spot) for each scan of the light spot SP which is the reflection surface of the polygon mirror PM. Therefore, by shifting the drawing lines SLn in the sub-scanning direction as in embodiment 2 in addition to correcting the drawing magnification as in embodiment 1 above after adjusting the inclination of each drawing line SLn by slightly rotating each of the adjacent scanning units Un about the irradiation center axes Le1 to Le6, the accuracy of the joining at the time of pattern drawing of the end portions of each drawing line SLn can be improved. Further, when a new pattern is overlappingly drawn on a base pattern for an electronic device which has been formed on the substrate P, the overlay accuracy can be improved.

In the above embodiment 2, the surface of the substrate P (the position where the light beam LBn is converged as the spot SP) and the plane Pip 'in fig. 21 are set in a conjugate relationship with each other, and further, the plane Pip' (Pip) and the

wavelength conversion elements

48 and 50 in the light source device lsa (lsb) and the emission end 46a of the fiber optical amplifier 46 are also set in a conjugate relationship with each other. Therefore, when the light flux LBn is projected as the spot SP to 1 point on the surface of the substrate P through the f θ lens FT and the cylindrical lens CYb in a state where 1 reflection surface of the polygon mirror PM is stationary in a fixed direction, even if the traveling direction of the harmonic light flux is angularly shifted due to a change in the crystal characteristics of the

wavelength conversion elements

48 and 50, the spot SP on the substrate P is not influenced by this and remains stationary. This means that the scanning start position in the main scanning direction of the spot SP or the drawing start position in response to the origin signal SD does not drift in the main scanning direction and remains stable. Therefore, the pattern can be drawn with stable accuracy over a long period of time.

[ embodiment 3 ]

Fig. 23 is a diagram showing a specific configuration of the scanning unit U1(Un) applied to the above embodiment 2 in embodiment 3, and is a diagram obtained by observing from a plane (XZ plane) orthogonal to a plane (plane parallel to the XY plane) including the scanning direction (deflection direction) of the light beam LB 1. In fig. 23, the optical axis AXf of the f θ lens system FT is arranged parallel to the XY plane, and the front end mirror M15 is arranged so as to bend the optical axis AXf by 90 degrees. In the scanning unit U1, a mirror M10, a beam expander BE, a parallel flat plate HVP with a variable inclination angle, an aperture stop PA, a mirror M12, a1 st cylindrical lens CYa, a mirror M13, a mirror M14, a polygon mirror PM (a reflection surface RP), an f θ lens system FT, a mirror M15, and a2 nd cylindrical lens CYb are provided along a light transmission path of the beam LB1 from an incident position of the beam LB1 to a surface to BE irradiated (a substrate P). The configuration of fig. 23 is basically the same as that of fig. 5, and some members and the like that need not be described are omitted. In the present embodiment, the parallel flat plate SR2 of the shift optical member SR provided in fig. 5 is a translucent parallel flat plate (quartz plate) HVP.

The light beam LB1 of the parallel light beam reflected in the-Z direction by the mirror IM1 shown in fig. 6 is incident on the mirror M10 inclined at 45 degrees with respect to the XY plane. The mirror M10 reflects the incident beam LB1 in the-X direction toward the mirror M12 separated from the mirror M10 in the-X direction. The light beam LB1 reflected by the mirror M10 passes through the beam expander BE and the aperture stop PA and enters the mirror M12. The beam expander BE expands the diameter of the transmitted light beam LB 1. The beam expander BE has a condenser lens BE1 and a collimator lens BE2 for making a beam LB1, which is converged by the condenser lens BE1 and then diverged, a parallel beam. The beam expander BE easily irradiates the beam LB6 to the opening portion of the aperture stop PA. A parallel plate HVP of quartz whose inclination angle can Be changed by a drive motor or the like, not shown, is disposed between the condenser lens Be1 and the collimator lens Be 2. By changing the tilt angle of the parallel flat plate HVP, the scanning line SLn, which is the scanning locus of the light spot SP scanned on the substrate P, can be shifted in the sub-scanning direction by a small amount (for example, several times to ten times the effective size Φ of the light spot SP).

The mirror M12 is disposed to be inclined at 45 degrees with respect to the YZ plane, and reflects the incident light beam LB1 in the-Z direction toward the mirror M13 separated from the mirror M12 in the-Z direction. The beam LB1 reflected in the-Z direction by the mirror M12 passes through the 1 st cylindrical lens CYa (1 st optical element) and reaches the mirror M13. The mirror M13 is disposed to be inclined at 45 degrees with respect to the XY plane, and reflects the incident light beam LB1 in the + X direction toward the mirror M14. The beam LB1 reflected by the mirror M13 is reflected by the mirror M14 and then projected to the polygon mirror PM. The 1 reflection surface RP of the polygon mirror PM reflects the incident light beam LB1 in the + X direction toward an f θ lens system FT having an optical axis AXf extending in the X axis direction.

The drawing line SLn can BE shifted in the sub-scanning direction by changing the inclination angle of the parallel flat plate HVP provided between the lens systems BE1, BE2 constituting the beam expander BE. Fig. 24A and 24B are diagrams illustrating a case where the line SLn is displaced due to the inclination of the parallel flat plate HVP, and fig. 24A is a diagram illustrating a state where the incident surface and the output surface of the parallel flat plate HVP, which are parallel to each other, are at 90 degrees with respect to the center line (principal ray) of the light flux LBn, that is, a diagram illustrating a state where the parallel flat plate HVP is not inclined in the XZ plane. Fig. 24B is a diagram showing a state in which the incident surface and the output surface of the parallel flat plate HVP, which are parallel to each other, are inclined from the center line (principal ray) of the light flux LBn by 90 degrees, that is, the parallel flat plate HVP is inclined at an angle η with respect to the YZ plane.

In fig. 24A and 24B, when the parallel flat plate HVP is not tilted (the angle η is 0 degrees), the optical axis AXe of the lens systems Be1 and Be2 is set to pass through the center of the circular opening of the aperture stop PA, and the center line of the light flux LBn incident on the beam expander Be is adjusted to Be coaxial with the optical axis AXe. The position of the rear focal point of the lens system Be2 is arranged to coincide with the position of the circular opening of the aperture stop PA. The position of the aperture stop PA is set so as to be substantially the pupil position as viewed from the position of the reflection surface RP of the polygon mirror PM (or the position of the front focal point of the f θ lens system FT) in the sub-scanning direction by the 1 st cylindrical lens CYa. On the other hand, in the main scanning direction, the aperture stop PA is disposed so as to be optically conjugate with the position of the front focal point of the f θ lens system FT, that is, the position of the entrance pupil. Therefore, when the parallel plate HVP is inclined at the angle η, the center line of the light beam LBn (here, divergent light beam) that has passed through the parallel plate HVP and entered the lens system Be2 is slightly shifted in parallel in the-Z direction with respect to the optical axis AXe, the light beam LBn emitted from the lens system Be2 is converted into a parallel light beam, and the center line of the light beam LBn is slightly inclined with respect to the optical axis AXe.

Since the position of the rear focal point of the lens system Be2 is arranged so as to coincide with the position of the circular opening of the aperture stop PA, the light flux LBn (parallel light flux) obliquely emitted from the lens system Be2 continues to Be projected onto the circular opening without being shifted in the Z direction on the aperture stop PA. Therefore, the light beam LBn that has passed through the circular opening of the aperture stop PA is directed toward the 1 st cylindrical lens CYa of the subsequent stage at an angle slightly inclined in the sub-scanning direction in the XZ plane with respect to the optical axis AXe in a state where the intensity of the base of 1/e2 on the intensity distribution is correctly cut off. The aperture stop PA is a position on the reflection surface at which the light beam LBn (converging in the sub-scanning direction) incident on the reflection surface RP of the polygon mirror PM is slightly displaced in the sub-scanning direction, corresponding to the pupil position as viewed from the reflection surface RP of the polygon mirror PM, in accordance with the inclination angle in the sub-scanning direction of the light beam LBn that has passed through the circular opening of the aperture stop PA. Therefore, the light flux LBn reflected on the reflection surface RP of the polygon mirror PM enters the f θ lens system FT in a state slightly shifted in the Z direction with respect to a surface parallel to the XY plane including the optical axis AXf of the f θ lens system FT shown in fig. 23. As a result, the light beam LBn incident on the 2 nd cylindrical lens CYb is slightly inclined in the sub-scanning direction, and the position of the spot SP of the light beam LBn projected onto the substrate P can be slightly shifted in the sub-scanning direction.

[ 4 th embodiment ]

Fig. 25 is a block diagram showing a configuration of a controller 16 of an exposure apparatus EX (pattern writing apparatus) according to embodiment 4. In fig. 25, the polygon mirror drive control section 100, the selection element drive control section 102, the light flux control device 104 (exposure control section 116), the mark position detection section 106, and the rotational position detection section 108 constituting the control device 16 are the same as those shown in fig. 9. In fig. 25, only a state in which the light beam LBa from the light source device LSa is supplied to the scanning unit U1 is representatively schematically shown, the optical element AOM1 for selection, the collimator lens CL1, and the unit-side entrance mirror IM1 are arranged in the same manner as in fig. 20, and the scanning unit U1 from the reflecting mirror M10 to the 2 nd cylindrical lens CYb is configured in the same manner as in fig. 23. In the present embodiment, a servo control system DU including a piezoelectric motor and the like for tilting a parallel plate HVP as a mechanical-optical beam phase shifter in the scanner unit U1 by a specific stroke and a basal layer measuring unit MU are provided. The ground layer measuring unit MU has a circuit configuration for rapidly digitally sampling a change in waveform of a photoelectric signal from the photodetector DT (see fig. 5) in the scanning unit U1, and measures a position in the main scanning direction or the sub-scanning direction of the ground pattern or a relative position error (overlay error) between a new pattern of the overlay exposure and the ground pattern, based on a change in intensity of reflected light generated when the spot SP scans the ground pattern (corresponding to the metal layer, the insulating layer, the semiconductor layer, and the like) formed on the substrate P for the overlay exposure. The measurement result measured by the ground layer measurement unit MU, particularly, information on the overlay error is used to generate the correction signal FSS to be applied to the drive circuit 102A in the selective element drive control unit 102 shown in fig. 20. By providing the photodetector DT (see fig. 5) and the base layer measurement unit MU as the position measurement unit for each scanning unit Un in this manner, the overlay accuracy in the exposed region W of the alignment mark MKn (the device formation region in fig. 4) can be confirmed, and the movement position of the substrate P (the movement position of the device formation region W) during pattern exposure can be confirmed.

Since the parallel flat plate HVP is provided for each of the scanning units Un, the dimension in the sub-scanning direction of the pattern drawn on the substrate P can be expanded and contracted at a slight rate by continuously changing the inclination angle η of the parallel flat plate HVP for each scanning unit Un. Therefore, even when the substrate P is locally stretched in the longitudinal direction (sub-scanning direction) of the substrate P, the overlay accuracy in overlaying the pattern for the layer 2 on the base pattern (layer 1 pattern) for the electronic device formed on the substrate P together with the alignment mark MKn can be favorably maintained. As shown in fig. 4, for example, the local expansion and contraction in the longitudinal direction (sub-scanning direction) of the substrate P can be measured by detecting alignment marks MK1 and MK4 formed at a constant pitch (for example, 10mm) on both sides in the width direction of the substrate P in the longitudinal direction by using an alignment microscope AM1m shown in fig. 25. Specifically, as shown in fig. 4, alignment marks MK1 and MK4 are sequentially picked up by the alignment microscopes AM11 and AM14 using an image pickup device, and changes in the longitudinal direction of the mark position (such as changes in the pitch of the mark) are analyzed and measured by the mark position detection unit 106, the rotational position detection unit 108, and the like, using the exposure control unit 116. Therefore, in accordance with the local expansion/contraction amount (scaling error) in the transport direction of the substrate P, the exposure control unit 116 gives a control command to the servo control system DU to sequentially tilt the parallel flat plate HVP in accordance with the movement position (or movement amount) in the sub-scanning direction of the substrate P. Thus, the pattern drawing position and the moving position of the substrate P can be adjusted gradually in the sub-scanning direction in conjunction with each other, and the lowering of the precision of the overlay exposure with respect to the substrate P having a large expansion and contraction can be suppressed.

The parallel flat plate HVP may be used to adjust the intervals in the sub-scanning direction (the substrate P conveyance direction) between the odd-numbered lines SL1, SL3, SL5 and the even-numbered lines SL2, SL4, SL 6. For example, when the conveyance speed of the substrate P is gently changed, the pattern drawn by the odd-numbered drawing line and the pattern drawn by the even-numbered drawing line are shifted in the sub-scanning direction by the order of micrometers due to the speed change, and the bonding accuracy is deteriorated. Therefore, the rotational position detecting unit 108, which counts the measurement signals from the encoders ENja, ENjb (only EN1a, EN2a are representatively shown in fig. 25) that measure the rotational position of the rotary drum DR, may detect a fluctuation in the rotational speed of the rotary drum DR (a speed fluctuation of the substrate P), and may drive the tilt of the parallel plate HVP by the servo control system DU according to the increase/decrease amount of the fluctuation.

Further, the mechanical optical beam phase shifters (beam position adjusting means, 1 st adjusting means) using the parallel flat plate HVP may be used for coarse adjustment of the position of the spot SP in the sub-scanning direction, and the photoelectric beam phase shifters (beam position adjusting means, 2 nd adjusting means) using the selection optical element AOM1 shown in fig. 25 (or the acousto-optic deflection elements AODs shown in fig. 16, the photoelectric elements ODn, KDn shown in fig. 17, and the like) may be used for fine adjustment of the position of the spot SP in the sub-scanning direction. When the parallel plate HVP and the selection optical element AOM1(AOMn) are combined as shown in fig. 25, the parallel plate HVP as a mechano-optical beam phase shifter can shift the light spot SP on the substrate P by several tens of pixels (for example, about ± 100 μm) in the sub-scanning direction within a tiltable stroke range, while the selection optical element AOM1(AOMn) as an electro-optical beam phase shifter can shift the light spot SP on the substrate P rapidly by a minute range of, for example, several pixels (several times the size Φ of the light spot SP) in the sub-scanning direction.

The position of the spot SP in the sub-scanning direction can be quickly fine-adjusted every 1 scan by changing the value of the correction signal FSS every time the incident permission signal LPn shown in fig. 10 is generated by using the electro-optical beam phase shifter of the optical element for selection (acousto-optical deflecting element) AOMn, AODs, or the electro-optical elements ODn, KDn, or the like. Therefore, the drawing quality when drawing a fine pattern can be improved, and particularly, the bonding error when bonding the pattern drawn by each of the plurality of drawing lines SLn in the main scanning direction can be reduced. In the present embodiment, the degree of the bonding error can be measured substantially immediately by using the photodetector DT and the ground layer measuring unit MU shown in fig. 25, for example. For example, in fig. 4, when a base pattern (layer 1 pattern) is already formed on the substrate P when the patterns drawn on the drawing lines SL1 and SL2 are joined in the sub-scanning direction, the joining error of the patterns drawn on the drawing lines SL1 and SL2 with respect to the base pattern can be confirmed by comparing the information of the overlapping error of the joined portion measured by the base layer measurement unit MU (fig. 25) provided in the scanning unit U1 that performs pattern drawing with the drawing line SL1 with the information of the overlapping error of the joined portion measured by the same base layer measurement unit MU provided in the scanning unit U2 that performs pattern drawing with the drawing line SL 2.

In the case of fig. 4, the position in the sub-scanning direction on the substrate P drawn by the drawing line SL1 is drawn by the drawing line SL2 after the substrate P has moved by the amount of the interval between the drawing line SL1 and the drawing line SL2 in the sub-scanning direction, and therefore, a time difference occurs in the movement time of the interval amount, but the tendency of the bonding error (whether the error is large) can be grasped when the measurement of the overlay error by the base layer measurement unit MU is performed every appropriate movement amount of the substrate P (for example, every 1mm or every 5 mm). In the case where the tendency of the bonding error to increase is exhibited, the position of the spot SP scanned along at least one of the drawing line SL1 and the drawing line SL2 in the sub-scanning direction may be finely adjusted by adjusting the correction signal FSS applied to the drive circuit 102A (see fig. 20) in the selector drive control unit 102 provided corresponding to at least one of the scanning unit U1 and the scanning unit U2 based on the information of the bonding error measured by the ground layer measurement unit MU so that the bonding error decreases.

[ another modification 1 ]

In each of the above embodiments and modifications, the tiltable parallel flat plate Sr2 or HVP as a beam phase shifter (position adjusting member, 1 st adjusting member) of mechanical optics that shifts the light beam LBn (the spot SP) in the sub-scanning direction is provided in the optical path from the mirror M10 to the polygon mirror PM in the scanning unit Un, but may be provided in the optical path from the polygon mirror PM to the substrate P. Further, the mechanical-optical beam phase shifter may be provided in the optical path from the cell-side incident mirror IMn (IM1 to IM6) of the beam switching portion BDU to the mirror M10 of the scanning cell Un. As described above, the mechanical-optical beam phase shifter (the 1 st adjusting means, the 1 st adjusting optical means) can shift the spot SP of the light beam LBn in the sub-scanning direction over a relatively wide range, but since an error depending on the mechanical accuracy easily remains, the electro-optical beam phase shifter (the 2 nd adjusting means, the 2 nd adjusting optical means) can be used together to reduce the remaining error. In this case, the electro-optical beam phase shifter is preferably arranged in front of the mechanical-optical beam phase shifter along the optical path of the light beam LBa, LBb proceeding from the light source device LSa, LSb.

[ another modification 2 ]

In each of the scanning units (drawing units) Un, the lens systems BE1, BE2 constituting the beam expander BE are provided as a convex lens system having positive refractive power as shown in fig. 23, but as shown in fig. 26, the lens system BE1 into which the light beam LBn reflected by the mirror M10 is incident may BE replaced with a concave lens system BE 1' having negative refractive power. Fig. 26 is a diagram schematically showing an enlarged state of the light beam LBn in the optical path from the mirror M10 to the aperture stop PA in the optical path within the scanning unit (drawing unit) Un shown in fig. 23. The light beam LBn reflected by the mirror M10 becomes a fine parallel beam having an effective beam diameter of 1mm or less and enters the concave lens system Be 1'. The lens system Be1 'causes the incident light beam LBn to Be incident on the convex lens system Be2 having positive refractive power while diverging according to the focal length of the lens system Be 1'. By matching the position of the front focal length of the concave lens system Be 1' with the position of the front focal length of the convex lens system Be2, the light beam LBn emitted from the convex lens system Be2 becomes a parallel light beam having an effective beam diameter enlarged as illustrated in fig. 23 and is directed toward the aperture stop PA. The beam expander using the concave lens system Be 1' and the convex lens system Be2 can shorten the physical distance between the 2 lens systems compared to the beam expander using the 2 convex lens systems Be1, Be 2.

In the beam expander BE of the scanning unit (drawing unit) Un shown in fig. 23, only the parallel flat plate HVP that mechanically and optically displaces the scanning line SLn, which is the scanning locus of the spot SP, in the sub-scanning direction (X direction) on the substrate P is provided. However, in order to finely adjust the entire drawing line SLn in the main scanning direction (Y direction), the parallel plate HVPx serving as the phase shifter for the X direction and the parallel plate HVPy serving as the phase shifter for the Y direction may Be provided between the lens system Be 1' and the lens system Be2 side by side along the optical axis AXe. In this case, the rotation center axis Sy for tilting the parallel plate HVPx and the rotation center axis Sx for tilting the parallel plate HVPy are set to be orthogonal to each other in a plane orthogonal to the optical axis AXe (parallel to the YZ plane).

[ another modification 3 ]

As shown in fig. 27, a parallel plate HVPy as a mechanical-optical phase shifter for fine-adjusting the entire drawing line SLn in the main scanning direction (Y direction) may be provided after the f θ lens system FT. Fig. 27 is a diagram showing an optical system arrangement from the polygon mirror PM in the scanning unit (drawing unit) Un shown in fig. 23 to the substrate P. After the f θ lens system FT, the light flux LBn scans in the main scanning direction (Y direction), and therefore, as shown in fig. 27, when the parallel flat plate HVPy is provided between the mirror M15 and the 2 nd cylindrical lens CYb, the parallel flat plate HVPy is set to a length approximately equal to the Y-direction dimension of the cylindrical lens CYb. Further, the rotation center axis Sx for inclining the parallel flat plate HVPy of fig. 27 in a plane parallel to the YZ plane is set parallel to the X axis, and is set so as to be orthogonal to the optical axis AXf of the f θ lens system FT which becomes parallel to the Z axis after being bent at the mirror M15.

Claims

1. A pattern drawing device in which a plurality of drawing units that scan a drawing light beam condensed on a substrate as a light spot in a1 st direction to draw a pattern are arranged in the 1 st direction, and the pattern drawn by the plurality of drawing units is joined in the 1 st direction and drawn by moving the substrate in a2 nd direction intersecting the 1 st direction, the device comprising:

a position measuring unit that measures a position of an exposed area on the substrate to be drawn by the plurality of drawing units;

a first adjustment means for adjusting the position of the light spot in the 2 nd direction during the movement of the substrate based on each of the drawing units based on the position measured by the position measurement means so as to reduce a position error of the pattern drawn by each of the drawing units with respect to the exposure area; and

and a2 nd adjustment means for adjusting the position of the light spot by the drawing means in the 2 nd direction with higher responsiveness than the 1 st adjustment means during movement of the substrate so as to reduce a bonding error in the 2 nd direction of the pattern drawn by the drawing means.

2. The pattern rendering device of claim 1, wherein

The substrate is a flexible sheet substrate having a longitudinal direction in the 2 nd direction, and has a plurality of marks formed at specific design intervals along the 2 nd direction, and

the position measuring unit includes a mark position detecting unit that sequentially detects the positions of the plurality of marks on an upstream side of a drawing position based on the pattern of the drawing unit in a moving direction of the sheet substrate.

3. The pattern rendering device of claim 2, wherein

The 1 st adjusting means adjusts the position of the light spot in the 2 nd direction based on an error in the spacing in the 2 nd direction of each of the plurality of marks detected by the mark position detecting section with respect to the design spacing.

4. The pattern rendering device of claim 3, wherein

Each of the plurality of drawing units includes: a rotary polygon mirror having a plurality of reflection surfaces that change an angle of the drawing light beam in a direction corresponding to the 1 st direction and reflect the drawing light beam; and a scanning optical system that condenses the drawing beam reflected by the reflecting surface of the rotary polygon mirror into a spot on the substrate; and is

The 1 st adjustment means is a mechanical optical phase shifter that mechanically drives a mechanical optical phase shifter to shift a position of the drawing light beam projected onto a reflection surface of the rotary polygon mirror in a direction corresponding to the 2 nd direction on the reflection surface of the rotary polygon mirror.

5. The pattern drawing device according to claim 4, further comprising a light source device for generating the drawing light beam, and

the 2 nd adjustment member is a photoelectric phase shifter that is provided between the light source device and the 1 st adjustment member and shifts a position of the drawing light beam projected onto the reflection surface of the rotary polygon mirror in a direction corresponding to the 2 nd direction on the reflection surface of the rotary polygon mirror by electrical physical property control.

6. The pattern rendering device of claim 5, wherein

The photoelectric phase shifter is an acousto-optic modulator or an acousto-optic deflection element capable of adjusting a deflection angle in accordance with the frequency of high-frequency power applied as a drive signal.

7. The pattern rendering device of claim 4, wherein

Forming a base pattern on the substrate together with the marks,

each of the plurality of drawing units includes a photodetector for detecting a change in reflected light generated when a light spot of the drawing light beam scans the base pattern while a new pattern to be subjected to the overlay exposure is drawn on the base pattern by the scanning of the light spot, and the photodetector detects a change in reflected light generated when the light spot scans the base pattern

The position measuring unit includes a base layer measuring unit that measures a bonding error between the new patterns drawn by the drawing units with reference to the base pattern, based on photoelectric signals from the photodetectors of the drawing units.

8. The pattern rendering device of claim 7, wherein

The 2 nd adjusting means adjusts the position of the light spot in the 2 nd direction so that the bonding error measured by the base layer measuring unit is reduced.

9. A pattern drawing device in which a plurality of drawing units for projecting drawing beams to draw a pattern within a drawing range shorter than the width of a substrate in a1 st direction are arranged in the 1 st direction, and the pattern drawn by each of the plurality of drawing units is joined and drawn in the 1 st direction by moving the substrate in a2 nd direction perpendicular to the 1 st direction, the device comprising:

a mechanical-optical phase shifter provided in each of the plurality of drawing units, for reducing a position error of the pattern drawn by each of the plurality of drawing units with respect to the exposure area, and configured to shift a projection position of the drawing beam projected from each of the drawing units in the 2 nd direction by mechanical driving during movement of the substrate, based on the position measured by the position measuring unit; and

and an electro-optical phase shifter configured to shift a projection position of the drawing light beam projected from each of the drawing units in the 2 nd direction by a control of a responsive and electrical physical property higher than that of the mechanical-optical phase shifter during movement of the substrate, in order to reduce a bonding error in the 2 nd direction of the pattern drawn by each of the plurality of drawing units.

10. The pattern rendering device of claim 9, wherein

The substrate has a plurality of marks formed at specific design intervals along the 2 nd direction, and

the position measuring unit includes a mark position detecting unit that sequentially detects positions of the marks on an upstream side of a drawing range of the pattern by each of the drawing units in a moving direction of the substrate.

11. The pattern rendering device of claim 10, wherein

The mechanical optical phase shifter adjusts the projection position of the drawing light beam in the 2 nd direction based on an error in the interval in the 2 nd direction of each of the plurality of marks detected by the mark position detection unit with respect to the design interval.

12. The pattern rendering device of claim 10 or 11, wherein

The mechanical optical phase shifter is a transparent parallel flat plate capable of adjusting the shift amount of the drawing beam according to the size of the inclination angle; and is

13. The pattern rendering device of claim 12, wherein

Forming a base pattern on the substrate together with the marks,

each of the plurality of drawing units includes a photodetector for detecting a change in reflected light generated when the base pattern is irradiated with the drawing light beam while the base pattern is projected with the drawing light beam corresponding to a new pattern to be subjected to the overlay exposure, and the photodetector detects a change in reflected light generated when the base pattern is irradiated with the drawing light beam

The position measuring unit includes a base layer measuring unit that measures a bonding error between the new patterns drawn by the drawing units with reference to the base pattern, based on a photoelectric signal from the photodetector of each of the drawing units.

14. The pattern rendering device of claim 13, wherein

The photoelectric phase shifter adjusts the projection position of the drawing beam in the 2 nd direction so that the bonding error measured by the underlayer measuring unit is reduced.