JP2007003934A - Multihead exposure device and exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multihead exposure device and an exposure method for attaining fast exposure while reducing unnecessary scanning. <P>SOLUTION: A stage 3 continuously moves in a main scanning direction 5 to continuously operate a substrate 3 as well as moves stepwise in a sub scanning direction 6 perpendicular to the main scanning direction. A plurality of exposure heads 4 are stacked in a compact form in a direction 7 perpendicular to both of the sub scanning direction 6 and the substrate 2. Each exposure head 4 is composed of a light source, a collimation lens, a mirror, and a DMD (digital micromirror device) as a spatial modulator. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an exposure apparatus and an exposure method. More specifically, for example, the present invention relates to a multi-head exposure apparatus and an exposure method having a plurality of exposure heads for irradiating a light beam onto a substrate of a liquid crystal display or a general circuit board to pattern a predetermined pattern shape.

  Conventionally, for example, in the manufacture of a liquid crystal display or a semiconductor integrated circuit, a module or a circuit board is formed by sequentially laminating a resin, metal wiring or the like patterned in a predetermined pattern shape on a substrate. In patterning, a photolithography technique including a resist film coating process, an exposure process using a photomask, and a resist pattern developing process is used.

  As an exposure apparatus used for forming an exposure pattern in the exposure process, an exposure apparatus called a stepper that employs a projection exposure method in which a predetermined mask pattern is projected onto a substrate is widely used. Normally, in exposure pattern formation of these liquid crystal displays and semiconductor integrated circuits, overlay exposure is performed in which an upper exposure pattern is positioned and superimposed on a lower exposure pattern.

  Further, in these exposure apparatuses, exposure is performed using a single exposure head so as to cover a large substrate area by step and repeat, and it is necessary to repeat a huge number of repeat exposures. In order to expand the exposure area, an exposure apparatus has also been proposed in which several to tens of exposure heads are arranged in a horizontal plane to achieve high speed.

  On the other hand, such a projection exposure apparatus usually requires a plurality of expensive photomasks for each model. Therefore, in mass production, the photomask cost borne by each product can be kept low by allocating the photomask cost to the selling price of each product. However, in recent years, product specifications have been diversified with the diversification of user values. For this reason, in the case of small-quantity, multi-product production, the number of products to which photomask costs are allocated is smaller than that in the case of mass production, so the photomask cost to be paid per product is large. In addition, since it is necessary to recreate the photomask to correct the exposure pattern, a huge amount of money is required both in terms of money and time. Furthermore, since a certain period of time is required for designing a photomask, it is difficult to quickly respond to market needs.

  Therefore, in recent years, two-dimensional spatial light typified by a mirror device called DMD (Digital Micro-mirror Device) is used as a means for reducing the financial and time costs caused by using a photomask during exposure. An exposure apparatus using a modulation element (SLM) has been proposed. In this exposure apparatus, a desired exposure pattern can be irradiated onto a substrate without using a photomask based on CAD data such as a wiring pattern. Therefore, it is possible to directly draw an exposure pattern on the substrate.

Here, for example, Patent Document 1 discloses a scanning exposure apparatus in which a plurality of exposure heads equipped with DMDs are arranged in a horizontal plane based on the idea of expanding an exposure area without using an expensive photomask. Has been. In the apparatus of Patent Document 1, since an exposure pattern is determined using a spatial light modulation element such as DMD, a photomask is unnecessary. In addition, since a plurality of exposure heads are arranged in a horizontal plane, a wide area exposure is possible by a single scan, and high speed is realized. Furthermore, the exposure areas by the respective exposure heads are arranged so that there is no gap in the direction perpendicular to the continuous scanning direction, thereby reducing the number of scans.
JP 2004-226520 A (published January 21, 2004)

  By the way, when the exposure resolution is low, a plurality of exposure heads can be arranged in the horizontal plane without gaps as in the exposure apparatus described in Patent Document 1.

  However, in the conventional exposure apparatus described in Patent Document 1, when the resolution is increased, the reduction magnification is increased, and the exposure area that can be exposed by one exposure head is narrowed. As a result, the number of scans must be increased by the amount that the exposure area is narrowed, which hinders high-speed exposure.

  Alternatively, it is possible to prevent the number of scans from increasing by increasing the number of exposure heads by the amount that the exposure area has become narrower. There is a limit to the number of exposure heads that can be arranged. That is, there is a problem in that there are cases where the number of exposure heads cannot be increased by the narrowed amount.

  Furthermore, although it is possible to arrange the exposure heads so as to protrude from the width of the substrate, when exposing one substrate using the exposed exposure head, all the exposure heads scan over the substrate. There is a problem that the range becomes large and also hinders high-speed exposure.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a multi-head exposure apparatus and an exposure method capable of realizing high-speed exposure by reducing unnecessary scanning as much as possible.

  In order to solve the above-described problems, the exposure apparatus of the present invention has a two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, and each light of the two-dimensional spatial light modulation element. A plurality of exposure heads capable of collectively exposing a desired pattern for a predetermined region by inputting pattern data to the modulation element, and scanning means for relatively scanning the exposure head and the object to be exposed In the multi-head exposure apparatus that performs exposure while continuously scanning, the plurality of exposure heads are stacked in a direction perpendicular to the exposure surface of the object to be exposed.

  With one exposure head, it is possible to expose a predetermined area on the object to be exposed by the two-dimensional spatial light modulator. Therefore, when the exposure heads are arranged side by side only in a plane, when the size of the exposure head plane is larger than the predetermined area, the total exposure area is the maximum number of the predetermined area exposure heads arranged on the plane. X It is a predetermined area, and the total exposure area cannot be increased beyond that. When the exposure head is disposed beyond the object to be exposed, the scanning range is wasted.

  However, in the present invention, since the plurality of exposure heads are stacked in the direction perpendicular to the exposure surface of the object to be exposed, the number of exposure heads can be greatly increased in the height direction. Since a large area can be exposed by a single scan by the increased number of exposure heads, high-speed exposure can be realized.

  Therefore, it is possible to provide an exposure apparatus that can realize high-speed exposure by reducing unnecessary scanning as much as possible.

  In the exposure apparatus of the present invention, each exposure head includes an irradiation unit having at least a mirror for bending the optical path of the exposure beam and an objective lens for condensing the exposure beam on the object to be exposed. It is preferable that the projection unit is provided so as to protrude from the head body, and the irradiation unit of each exposure head is disposed so that the optical paths of the exposure beams do not interfere with each other.

  Thus, it becomes possible to irradiate the object to be exposed with the entire exposure beam without the optical paths of the exposure heads stacked in the upper layer being obstructed by the exposure heads in the lower layer. Therefore, exposure can be performed more efficiently.

  In the exposure apparatus of the present invention, the width in the direction orthogonal to the continuous scanning direction in the planar shape of each irradiation unit is the width in the direction orthogonal to the continuous scanning direction in the planar shape of the exposure head body corresponding to the irradiation unit. Is preferably smaller.

  Accordingly, when the plurality of exposure heads are arranged on the object to be exposed, the optical paths of the exposure beams do not interfere with each other as long as the irradiation units are arranged so as not to overlap each other. Therefore, a larger number of the plurality of exposure heads can be arranged on the object to be exposed so that the optical paths of the exposure beams do not interfere with each other. Therefore, high-speed exposure can be performed efficiently.

  In the exposure apparatus of the present invention, it is preferable that the plurality of exposure heads are also arranged in a direction orthogonal to the continuous scanning direction in the exposure surface.

  As a result, the number of exposure heads can be increased both in the height direction and in the direction orthogonal to the continuous scanning direction, so that higher-speed exposure is possible by the increase in the number of exposure heads used for one exposure. Become.

  It is preferable that the plurality of exposure heads are also arranged in the continuous scanning direction.

  As a result, the number of exposure heads can be increased both in the height direction and in the continuous scanning direction, so that higher-speed exposure can be achieved by the increase in the number of exposure heads used for one exposure.

  In the exposure apparatus of the present invention, the plurality of exposure heads are arranged so that each exposure area of the plurality of exposure heads to the object to be exposed covers the entire width of the object to be exposed perpendicular to the continuous scanning direction. It is preferable.

  As a result, each exposure region on the object to be exposed covers the entire width of the object to be exposed that is perpendicular to the continuous scanning direction, so that step movement in the width direction is not necessary. Then, by relatively scanning the object to be exposed, the entire area of the object to be exposed can be exposed, so that higher-speed exposure can be realized.

  In the exposure apparatus of the present invention, the plurality of exposure heads may be configured such that each exposure region on the object to be exposed in the plurality of exposure heads partially covers the entire width of the object to be exposed perpendicular to the continuous scanning direction. It is preferable that the exposure heads are arranged so as to overlap.

  As a result, even when the exposure areas are misaligned due to misalignment between the plurality of exposure heads, the exposure areas are originally overlapped. If so, continue to overlap. Therefore, it is not necessary to create a gap between the exposure areas.

  In the exposure apparatus of the present invention, the exposure amount with respect to a predetermined region is changed by changing the intensity of light emitted from each light modulation element of a two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally. It is preferable that exposure intensity adjusting means for finely adjusting the exposure intensity by changing the above is provided.

  As a result, even if there is a variation in exposure intensity within an exposure area by one of the plurality of exposure heads or a variation in exposure intensity between exposure areas by the plurality of exposure heads, By changing the intensity of light emitted from the modulation element, it is possible to adjust the exposure intensity with respect to the predetermined area by each of the light modulation elements. That is, the exposure intensity can be adjusted so that the exposure is performed with a uniform intensity over the entire exposed object.

  Moreover, in order to solve the above-described problems, the exposure method of the present invention has a two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, and the two-dimensional spatial light modulation element By inputting pattern data to each light modulation element, a plurality of exposure heads that can collectively expose a desired pattern for a predetermined area are arranged, and the exposure head and the object to be exposed are relatively continuously scanned. In the exposure method in which exposure is performed, at least each of the exposure heads is exposed so that each exposure area of the plurality of exposure heads to the object to be exposed covers the entire width of the object to be exposed perpendicular to the continuous scanning direction. It arranges in the direction perpendicular | vertical to the exposure surface of a body, and it exposes to the said continuous scanning direction with respect to the said to-be-exposed body.

  According to the above invention, each exposure area on the object to be exposed covers the entire width of the object to be exposed that is orthogonal to the continuous scanning direction, so that step movement in the width direction is not necessary. Then, by relatively scanning the object to be exposed in the continuous scanning direction, it is possible to expose the entire area of the object to be exposed, so that higher-speed exposure can be realized.

  In the exposure method, the plurality of exposure heads may also be arranged in the continuous scanning direction, and a plurality of objects to be exposed may be exposed simultaneously using the plurality of exposure heads arranged in the continuous scanning direction. Is possible.

  Further, the exposure method of the present invention has a two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, and pattern data is stored in each light modulation element of the two-dimensional spatial light modulation element. In an exposure method in which a plurality of exposure heads capable of collectively exposing a desired pattern with respect to a predetermined area by inputting are arranged, and exposure is performed while relatively continuously scanning the exposure head and the object to be exposed. Preferably, the plurality of exposure heads are arranged at least in the continuous scanning direction, and the plurality of exposure objects are simultaneously exposed using the plurality of exposure heads arranged in the continuous scanning direction. .

  As a result, even if the plurality of exposure heads are arranged so as to protrude beyond the size of the object to be exposed in the continuous scanning direction, the protruding exposure head of the plurality of exposure heads is different from the object to be exposed. Can contribute to exposure. For this reason, useless scanning is eliminated, and almost all of the exposure heads can always perform exposure of some of the plurality of exposed objects, and very efficient exposure can be performed.

  Further, in the exposure method of the present invention, the plurality of objects to be exposed are successively conveyed in the continuous scanning direction in the order of, for example, a conveyor system, by the scanning unit for scanning the plurality of objects to be exposed. It is preferable to perform exposure.

  Thereby, when exposing the plurality of objects to be exposed at the same time with the plurality of exposure heads, in order to continuously expose the plurality of objects to be exposed, for example, in a conveyor manner, in order, Compared to reciprocating the scanning means to expose the object to be exposed, the time required for scanning can be reduced and very efficient exposure can be performed.

  Accordingly, it is possible to provide an exposure method capable of realizing high-speed exposure by reducing unnecessary scanning as much as possible.

  As described above, in the multi-head exposure apparatus of the present invention, the plurality of exposure heads are stacked in a direction perpendicular to the exposure surface of the object to be exposed.

  Therefore, the number of exposure heads that can be arranged within the width of the substrate can be greatly increased in the height direction, and the substrate can be exposed at a higher speed.

  Therefore, there is an effect that it is possible to provide an exposure apparatus that can reduce useless scanning as much as possible and realize high-speed exposure.

  In addition, as described above, the exposure method of the present invention includes the exposure heads so that each exposure region on the object to be exposed in the plurality of exposure heads covers the entire width of the object to be exposed perpendicular to the continuous scanning direction. In this method, the exposure object is exposed in the continuous scanning direction by arranging in at least a direction perpendicular to the exposure surface of the exposure object.

  Therefore, each exposure region on the object to be exposed covers the entire width of the object to be exposed that is perpendicular to the continuous scanning direction, and therefore step movement in the width direction is not necessary. Then, by relatively scanning the object to be exposed in the continuous scanning direction, it is possible to expose the entire area of the object to be exposed, so that higher-speed exposure can be realized.

  Therefore, it is possible to provide an exposure method that can reduce useless scanning as much as possible and realize high-speed exposure.

[Embodiment 1]
An embodiment of the present invention will be described with reference to FIGS. 1 to 4 as follows.

  FIG. 1 is a perspective view showing a schematic configuration of an exposure apparatus 1 including an optical system and a stage in the present embodiment, and FIG. 2 is a schematic diagram showing an optical system configuration of the exposure head in FIG. FIG. 3 is a side view from the X direction showing a light source and a spatial light modulator (SLM) part in FIG.

  The outline of the exposure apparatus 1 will be described with reference to FIG.

  In the exposure apparatus 1 according to the present embodiment, as shown in FIG. 1, a resist-coated substrate 2 (object to be exposed) is mounted on a mounting table 3 a of a stage 3 (scanning means) and faces the substrate 2. A plurality of exposure heads 4 are arranged.

  The stage 3 has a main scanning direction 5 (continuous scanning direction) in which exposure is performed by continuously scanning the substrate 2 and a sub scanning in which the main scanning direction 5 is perpendicular to the main scanning position and is moved stepwise or finely adjusted. Driving in two directions 6 is possible.

  The exposure heads 4 are arranged only in a plane in the conventional exposure apparatus, whereas in the present embodiment, the exposure heads 4 are arranged in two directions, ie, a sub-scanning direction 6 and a height direction 7 perpendicular to the substrate 2. Has been. The reason for this is as follows.

  For example, when a large number of exposure heads 4 are arranged and the exposure speed is increased by parallel processing, if the exposure heads are arranged in a plane, the number of exposure heads 4 arranged is small. When the width of the exposure head 4 is 10 cm, only 10 pieces are arranged on the substrate 2 having a width of 1 m. The exposure heads 4 arranged outside the substrate size cannot contribute to the exposure at the same time and are wasted. Further, when arranged in the main scanning direction 5 as well, it is necessary to scan extra for the deviation of the exposure position, resulting in a time loss. Therefore, the most efficient exposure can be achieved by arranging a large number of exposure heads 4 in parallel in the sub-scanning direction 6.

  In the configuration of the exposure apparatus 1 of the present embodiment, the exposure heads 4 are thus arranged in two directions, ie, the sub-scanning direction 6 and the height direction 7, and the exposure areas 24 described later are arranged in the sub-scanning direction 6. In a row parallel to For this reason, many exposure heads 4 can be arranged without protruding from the width of the substrate 2, and the scanning distance of the exposure head 4 in the main scanning direction 5 can be minimized.

  The internal configuration of the exposure apparatus 1 will be described.

  As shown in FIG. 2, the exposure apparatus 1 of the present embodiment has a light source unit 12 that can collectively expose a desired pattern with respect to a predetermined area on a substrate 2 as an object to be exposed, and for scanning the substrate 2. A stage 3 as scanning means and a scanning drive control device 30 for driving and controlling the stage 3 are provided. Since all the components constituting the light source unit 12 overlap each other and are difficult to see, the components other than the DMD 11 are not shown.

  In this embodiment, in order to scan the substrate 2 with respect to the exposure head 4, the stage 3a on which the substrate 2 is placed is moved on the stage 3. However, the present invention is not limited to this. A structure in which the entire exposure head 4 or a part thereof is moved while the mounting table 3a on which the substrate 2 is mounted may be fixed. That is, the scanning means of the present invention only needs to relatively scan the substrate 2 and the exposure head 4 (more precisely, the exposure beam).

  As shown in FIG. 3, the light source unit 12 of the exposure apparatus includes a light source 8, a collimation lens 9, a first mirror 10, and a DMD (Digital Micro-mirror Device) 11 as a spatial light modulator (SLM). Yes.

  The light source 8 has both a blue to ultraviolet wavelength component that is generally used for exposure of a resist and the like, and a red to infrared wavelength component that does not react with the resist. That is, in the present embodiment, the exposure apparatus 1 detects the position of the lower layer pattern by monitoring the already formed lower layer pattern on the substrate 2 by light irradiation, and based on the position detection of the lower layer pattern, A resist or the like can be exposed to form an upper layer pattern by correcting pattern data input to each light modulation element of a two-dimensional spatial light modulation element to be described later.

  For this reason, in the light source 8, a blue to ultraviolet wavelength component is used for exposure of a resist or the like, while a red to infrared wavelength component is used to monitor the lower layer pattern. More preferably, ultraviolet light is used for exposure and infrared light is used for monitoring. This is because ultraviolet light is often used for exposure. Although the details will be described later for monitoring the lower layer pattern, it is more preferable to irradiate using an infrared component since it can be monitored through the silicon layer.

  The light source 8 has been described as having both a blue to ultraviolet wavelength component and a red to infrared wavelength component, but a red to infrared light source for a lower layer monitor may be provided separately.

  As shown in FIG. 4, the DMD 11 is a two-dimensional spatial light modulation element (SLM) including a plurality of mirror elements 11a as two-dimensionally arranged light modulation elements. Each mirror element 11a of the DMD 11 By inputting pattern data from the computer 13, a desired pattern for a predetermined area can be exposed collectively.

  That is, the DMD 11 is composed of a large number of mirror elements 11a each capable of angle modulation, and can be set in an ON state that is incident on the projection lens 14 described later and an OFF state that is not incident by two types of angle settings. It has become. If the column Rn of the mirror element 11a and the row Lm of the mirror element 11a in FIG. 4 are turned on, the light is reduced and condensed by the projection lens 14 and the objective lens 17 shown in FIG. As a result, as shown in FIG. 4, exposure patterns 23 a and 23 b corresponding to the ON pattern of DMD 11 can be drawn on the resist on substrate 2. That is, the DMD 11 can be used like a variable mask.

  Note that one mirror element 11a of the DMD 11 has a size of about 10 to 20 μm, and if the lens system is designed so that a reduction magnification can be obtained according to a required resolution, the element size of the DMD 11 Even small patterns can be drawn. Although FIG. 4 illustrates an example of 8 × 8 mirror elements 11a, in actuality, a large number of mirror elements 11a of about 1000 × 1000 are provided.

  Note that the two-dimensional spatial light modulator (SLM) will be described here using the DMD 11, but is not limited to the DMD 11, and an element such as a liquid crystal may be used. Also, other elements may be used as long as they are spatially divided and can individually control light ON / OFF.

  The light emission operation in exposure and monitor light irradiation in the exposure apparatus 1 will be described.

  First, the light emitted from the light source 8 is converted into parallel light by the collimation lens 9, reflected by the first mirror 10, and then incident on the DMD 11. Each mirror element 11a of the DMD 11 is ON / OFF controlled by the computer 13 shown in FIG. 2 based on the pattern data to be exposed.

  As shown in FIG. 2, the light corresponding to the exposure pattern generated by the DMD 11 passes through the projection lens 14 and enters the dichroic mirror 15 serving as a separating unit. Then, after being partially reflected by the dichroic mirror 15, it is reflected by the second mirror 16, introduced into the objective lens 17, and imaged on the substrate 2 (object to be exposed) coated with resist. At this time, the ratio reflected by the dichroic mirror 15 is set to approximately 100% for the ultraviolet light component and 50% for the infrared light component, as will be described later. The substrate 2 is installed on the mounting table 3a of the stage 3, and the mounting table 3a is controlled by the scanning drive control device 30 so as to be movable back and forth. Therefore, the substrate 2 is scanned relative to the exposure beam. It has become so. In addition, a focusing mechanism 18 for driving the objective lens 17 is provided for focus adjustment for forming an image of light on the substrate 2 during exposure.

  On the other hand, a part of the light irradiated to the substrate 2 is reflected by the substrate 2 and returns to the dichroic mirror 15 through the objective lens 17 again. The dichroic mirror 15 is designed to reflect almost 100% of the ultraviolet light component, while reflecting 50% and transmitting 50% of the infrared light component. Therefore, almost 100% of the ultraviolet light component reflected and returned by the substrate 2 is reflected by the dichroic mirror 15 and returns to the light source unit 12 side. On the other hand, half of the infrared light component is reflected, but the other half is transmitted. The infrared light component transmitted through the dichroic mirror 15 passes through the imaging lens 19 and then enters the CCD camera 20 as a light receiving means.

  In the present embodiment, a filter 21 for cutting UV to visible light is provided in front of the CCD camera 20. The dichroic mirror 15 is normally made of a dielectric multilayer film or the like and designed to reflect the ultraviolet light component almost 100%, but slightly leaks light. The filter 21 is inserted in order to prevent the ultraviolet light component used for exposure that could not be reflected by the dichroic mirror 15 from entering the CCD camera 20.

  Note that a light modulator 22 such as a shutter may be provided before and after the projection lens 14 (after the drawing). The light modulator 22 is provided for the purpose of avoiding unnecessary light irradiation when using the light source 8 that does not have modulation means such as a lamp. This light modulator 22 may be used for the purpose of blocking light when light corresponding to the exposure pattern generated by the DMD 11 passes through a region that originally has no pattern, such as the peripheral portion of the substrate 2. . As will be described later, the optical modulator 22 is an effective device when exposure is performed by irradiating pulsed light while continuously scanning the stage 3 as an exposure method.

  On the other hand, as can be seen from FIG. 2, the exposure head 4 has a structure in which only the tip portion 4a as the irradiating portion protrudes from the exposure head body 4b from the second mirror 16 as the mirror. As can be seen from FIG. 1, the width of the tip portion 4a in the sub-scanning direction 6 is smaller than the width of the exposure head body 4b.

  That is, it is difficult to reduce the size because there are large parts such as the light source 8 on the exposure head body 4b side, and it is necessary to form a bent optical path before and after the DMD 11. However, the tip portion 4a only has the second mirror 16, the objective lens 17 and its focusing mechanism 18, and can be reduced in size. The number of exposure heads 4 that can be arranged in the sub-scanning direction 6 is determined by the width of the tip portion 4a. For example, if the width of the exposure head body 4b is 10 cm, when the exposure heads 4 are arranged in a plane, only 10 are arranged on a 1 m wide substrate. However, if the width of the tip portion 4a that can be narrower than the width of the exposure head body 4b is about 2 cm, 50 exposure heads 4 that are five times the previous estimate can be arranged in a row.

  As can be seen from FIG. 1, the length of the tip portion 4 a in the height direction 7 varies depending on the number of exposure heads 4 stacked in the height direction 7. The exposure head 4 arranged in the upper layer increases the distance between the second mirror 16 and the objective lens 17, and the height position of the objective lens 17 is set to be substantially the same in the exposure head 4 of any layer. . That is, in the upper-layer exposure head 4, the tip portion 4a protrudes below the exposure head body 4b.

  Next, the exposure method in the exposure apparatus 1 of this embodiment is demonstrated using FIG. 2 and FIG.

  First, as shown in FIG. 2, the substrate 2 is scanned by the stage 3. The stage 3 can be driven in a main scanning direction 5 that reciprocates at high speed, and a sub-scanning direction 6 that is perpendicular to the main scanning direction 5 and moves stepwise when the main scanning direction is switched. The respective displacement amounts in the main scanning direction 5 and the sub-scanning direction 6 are always monitored with high accuracy by a displacement detection means (not shown).

  Incidentally, the exposure is not always performed while the mounting table 3a is moving in the main scanning direction. As shown in FIG. 4, every time scanning of the exposure area 24 as a predetermined area by the DMD 11 is completed. Then, light is irradiated in a pulsed manner to perform exposure. In this way, by irradiating light in pulses while scanning, it is possible to effectively use all the mirror elements 11a of the DMD 11 without overlapping the exposure areas of the mirror elements 11a. Is possible. Further, since all the mirror elements 11a of the DMD 11 need only be switched ON / OFF according to the pulse interval, a time margin for position detection and a time margin for ON / OFF switching can be obtained. When a lamp is used as the light source 8, the light modulator 22 may be used to modulate the irradiation light from the lamp at a high speed, and the lamp may be used as a pulsed light source.

  As described above, the exposure in the exposure region 24 by one pulse is performed on the entire exposure target region of the substrate 2 while repeating the main scanning and the sub-scanning of the stage, and the substrate with the exposure region 24 by one pulse as one unit. The exposure of the entire substrate 2 is completed by filling the entire exposure target area 2.

At this time, the number of step movements in the sub-scanning direction 6 can be reduced by arranging many exposure heads 4 in the sub-scanning direction 6 and maintaining the width of the exposure region 24 as close to the width of the substrate 2 as possible. , Exposure speed can be increased. Since the exposure speed can be increased as the number of exposure heads arranged in a row increases within the width close to the width of the substrate 2, the exposure heads 4 are stacked in the height direction 7 and arranged in a row. The method of the present embodiment in which the number of exposure heads 4 is increased is effective for increasing the exposure speed.
[Embodiment 2]
Another embodiment of the present invention will be described below with reference to FIGS. 5 and 6A and 6B. Configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

  In addition to the configuration of the exposure apparatus 1 of the first embodiment, the exposure apparatus 1 of the present embodiment also has a plurality of exposure heads 4 arranged in the main scanning direction 5 as shown in FIG.

  In the exposure apparatus 1 according to the present embodiment, a number of exposure heads are provided not only in the sub-scanning direction 6 and the height direction 7 but also in the main scanning direction 5. Here, by arranging the exposure heads 4 in the main scanning direction 5, the scanning range of the stage 3 in the main scanning direction 5 is increased. As described above, the moving time corresponding to the increase in the scanning range in the main scanning direction 5 is lost. However, by increasing the number of exposure heads 4, it is possible to cancel the loss corresponding to the increase in the scanning range in the main scanning direction 5 and to speed up the process of exposing the entire substrate 2. This is because, since the main scanning direction 5 is continuous scanning, even if the movement distance in the main scanning direction is slightly increased, there is little time loss. Moreover, if the number of exposure heads 4 is doubled, for example, the number of scans of the main scan is halved, and the number of step movements performed once the main scan is stopped can be halved. In FIGS. 5 and 6, the arrangement of the exposure heads 4 in the main scanning direction 5 is shown using two rows, but of course, there may be three or more rows.

  Next, the exposure region 24 in the case of using a plurality of rows of exposure head groups 4c and 4d in the exposure apparatus 1 of the present embodiment will be described with reference to FIGS. 6 (a) and 6 (b). FIGS. 6A and 6B are schematic views showing the exposure region 24 by each exposure head 4. Reference numerals 24a and 24b indicate exposure possible areas by the first and second exposure head groups 4c and 4d, respectively, and 24c indicates exposed areas by the first and second exposure head groups 4c and 4d. The substrate 2 is scanned in the direction of the arrow in FIG. 6A with respect to the exposure possible area 24a by the first exposure head group 4c and the exposure possible area 24b by the second exposure head group 4d. To do.

  When exposure to the substrate 2 is started from the position of FIG. 6A, first, exposure to the substrate 2 by the exposure head group 4d in the second row is started. Then, when viewed from the substrate 2, the exposure head group 4d in the second row first exposes the substrate 2 (meaning the same position with respect to the main scanning direction, and with respect to the sub scanning direction). The exposure of the substrate 2 by the exposure head group 4c in the first row is started when the exposure head group 4c in the first row arrives. Then, in the state where the scanning has advanced to the position of FIG. 6B, the exposure of the exposed region 24c progresses step by step. Thereafter, the exposure by the exposure head group 4c in the first row is continued even after the exposure of the substrate 2 by the exposure head group 4d in the second row is stopped, so that a rectangular exposure area as a whole can be obtained. It becomes.

As shown in FIGS. 6 (a) and 6 (b), the gap between the exposure possible area 24a by the exposure head group 4c in the first row is filled with the exposure possible area 24b by the exposure head group 4d in the second row. It is most desirable to be able to cover the entire sub-scanning direction that requires exposure. In this way, the scanning can be performed only in the main scanning direction 5 by combining the exposure areas 24 by the exposure head groups 4c and 4d in a plurality of rows so as to cover the gaps generated in the sub-scanning direction 6 side of each row. There is no step movement in the sub-scanning direction 6, and the entire region of the substrate 2 can be exposed by only one scanning in the main scanning direction 5.
[Embodiment 3]
The following will describe another embodiment of the present invention with reference to FIG. Configurations other than those described in the present embodiment are the same as those in the first and second embodiments. For convenience of explanation, members having the same functions as those shown in the drawings of Embodiments 1 and 2 are given the same reference numerals, and descriptions thereof are omitted.

  In the exposure apparatus 1 of the present embodiment, in addition to the configuration of the exposure apparatus 1 of the first embodiment, the arrangement of the exposure heads 4 in the main scanning direction 5 is within the range of the substrate 2 as shown in FIG. It grows over.

  An exposure method in exposure apparatus 1 having the above configuration will be described with reference to FIG. 7 which is a side view showing a schematic configuration of exposure apparatus 1 in the present embodiment.

  25 indicates the length of the substrate in the main scanning direction 5, and 26 indicates the array width of the exposure heads 4 arranged in the main scanning direction 5.

In the second embodiment, it has been described that it is desirable to fill the exposure area of the width in the sub-scanning direction 6 on the substrate 2 with the exposure areas 24 of the exposure head groups 4c and 4d without any gaps. However, if the resolution is further increased and the exposure area 24 that can be shared by one exposure head 4 is further narrowed, the exposure head 4 in the main scanning direction 5 is filled to fill the exposure area of the width in the sub-scanning direction 6 without any gap. It becomes necessary to further increase the number of sequences. As a result, the arrangement width 26 of the exposure heads 4 sometimes becomes longer than the length 25 of the substrate. Here, when the exposure heads 4 are arranged in only one row in the main scanning direction 5, the main scanning may be performed within the range of the substrate length 25. In this way, a large number of the exposure heads 4 can perform the main scanning. When aligned in the direction 5, scanning for the arrangement length of the exposure heads 4 (more precisely, the span of the exposure region) is required in addition to the length 25 of the substrate. That is, it is necessary to perform scanning for all the exposure heads 4 to finish the exposure of the substrate 2. In this case, if only one substrate 2 is exposed by one exposure apparatus 1, there will always be an exposure head 4 that cannot contribute to exposure, resulting in waste. On the other hand, as shown in FIG. 7, it is assumed that a plurality of substrates 2 are exposed by one exposure apparatus 1, and the substrates 2 are successively flown by a stage 3 in a belt conveyor manner. Then, almost all of the exposure heads 4 can always perform some exposure of the plurality of substrates 2, and very efficient exposure can be performed.
[Embodiment 4]
The following will describe another embodiment of the present invention with reference to FIG. Configurations other than those described in the present embodiment are the same as those in the first to third embodiments. For convenience of explanation, members having the same functions as those shown in the drawings of Embodiments 1 to 3 are given the same reference numerals, and descriptions thereof are omitted.

  FIG. 8 is a schematic diagram showing an exposed region 24c by each exposure head 4 in the present embodiment, and shows a modification of FIG. 6B.

  In FIG. 6B, the example in which the exposure regions 24 by the exposure heads 4 are arranged without gaps in the sub-scanning direction 6 has been described. However, due to the position adjustment error between the exposure heads 4 or the like. In some cases, the positional relationship between the respective exposure areas 24 by the respective exposure heads 4 is shifted. In other words, if the exposure areas 24 are set so as to be aligned with no gaps, gaps may occur between the exposure areas 24 when a positional shift occurs.

  Here, if the exposure patterns 23a and 23b on the substrate 2 are missing, problems such as poor continuity may occur. Therefore, it is absolutely necessary to avoid a situation in which a gap is generated between the exposure regions 24.

  On the other hand, in the present embodiment, as shown in FIG. 8, the exposed areas 24c by the respective exposure heads 4 are set so as to slightly overlap each other. By doing so, it is possible to prevent a gap from being formed between the exposure regions 24 even when the positional relationship between the exposure regions 24 is shifted. In this example, the exposure patterns are superposed in the sub-scanning direction 6, but also when the exposure patterns 23a and 23b are arranged in the main scanning direction 5 (as in the example of FIG. 4), pulse irradiation during exposure is performed. The same effect can be obtained by adjusting the timing so that the exposure patterns slightly overlap each other.

  In addition, in the region where the exposure region 24 overlaps, the exposure amount may be gradually changed so that the exposure intensity is weaker than the region where the exposure region 24 does not overlap. If the exposure area 24 is overlapped with the normal exposure intensity, the exposure area 24 overlaps with the exposure intensity that is twice that of the non-overlapping area, resulting in overexposure and high-definition exposure. There is a case. However, for example, in the region where the exposure regions 24 overlap, if the exposure intensity is changed so as to decrease with a linear gradient, the overlapped and added exposure intensity becomes the same as the other portions. Therefore, even when the positions of the exposure regions 24 are shifted from each other, the difference in exposure intensity between the region where the exposure regions 24 overlap and the region where they do not overlap can be reduced. Further, in order to change the exposure intensity, for example, in the case of DMD11, the ON / OFF time ratio of each mirror element 11a is changed (by performing finer control, the OFF state is set for a part of the ON state time. And the angle of the mirror element 11a is set not only to 1/0 corresponding to ON / OFF, but also to an intermediate position, and the exposure amount is changed by adjusting the amount of light emitted. A method etc. can be considered.

  Further, when exposure is performed using a large number of exposure heads 4 in this way, in addition to variations in exposure intensity within the exposure region 24 by the exposure head 4, the exposure head 4 has different exposure areas 24. Variations in exposure intensity are likely to occur. Even when the exposure intensity varies between the exposure areas 24, the exposure intensity is adjusted for each exposure area 24 using the DMD 11 as described above, so that uniform exposure is performed in all the exposure areas 24. Strength can be obtained. For fine adjustment such as correction of the exposure intensity of the entire exposure region, the exposure amount adjustment method based on the change in the ON / OFF time ratio of the mirror and the intermediate position setting can be used.

  Note that the present invention is not limited to the above-described embodiments, and various modifications within the scope of the claims are possible. The technical means disclosed in different embodiments are appropriately combined. The obtained embodiment is also included in the technical scope of the present invention.

  The multi-head exposure apparatus and exposure method of the present invention can be suitably used in an industrial field for manufacturing a substrate for a liquid crystal display, a general circuit board, and the like, and an industrial field for manufacturing an exposure apparatus.

1 is a perspective view showing a schematic configuration of an exposure apparatus in an embodiment of the present invention. It is the schematic which shows the optical system structure of the exposure head in FIG. It is a side view from the X direction of FIG. 2 which shows the part of the light source and spatial light modulation element (SLM) in FIG. It is a figure for showing typically operation of DMD which is a kind of SLM. It is a perspective view which shows schematic structure of the exposure apparatus in other embodiment of this invention. It is a schematic diagram which shows the exposure area | region by each exposure head. It is a side view which shows the schematic structure of the exposure apparatus in other embodiment of this invention. It is a schematic diagram which shows the exposure area | region by each exposure head in other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exposure apparatus 2 Substrate (object to be exposed)
3 stages (scanning means)
3a mounting table 4 exposure head 4a tip part (irradiation part)
4b Exposure head body 5 Main scanning direction (continuous scanning direction)
6 Sub-scanning direction 7 Height direction 8 Light source 9 Collimation lens 10 First mirror 11 DMD (two-dimensional spatial light modulator)
11a Mirror element (light modulation element)
12 light source unit 13 computer (exposure intensity adjusting means)
14 Projection lens 15 Dichroic mirror 16 Second mirror (mirror)
17 Objective lens 18 Focusing mechanism 19 Imaging lens 20 CCD camera 21 Filter 22 Light modulators 23a and 23b Exposure pattern 24 Exposure area (predetermined area)
25 Substrate length 26 Exposure head array width 30 Scanning drive control device

Claims (11)

A two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, and by inputting pattern data to each light modulation element of the two-dimensional spatial light modulation element, a desired region can be obtained In a multi-head exposure apparatus that includes a plurality of exposure heads that can collectively expose the pattern, and a scanning unit that relatively scans the exposure head and the object to be exposed, and performs exposure while continuously scanning ,
The multi-head exposure apparatus, wherein the plurality of exposure heads are stacked in a direction perpendicular to an exposure surface of the object to be exposed. Each of the exposure heads is provided with an irradiating portion that protrudes from the exposure head main body and includes at least a mirror for bending the optical path of the exposure beam and an objective lens for condensing the exposure beam on the object to be exposed. With
2. The multi-head exposure apparatus according to claim 1, wherein the irradiation section of each exposure head is arranged so that the optical paths of the exposure beams do not interfere with each other.   The width in the direction orthogonal to the continuous scanning direction in the planar shape of each irradiation unit is smaller than the width in the direction orthogonal to the continuous scanning direction in the planar shape of the exposure head body corresponding to the irradiation unit. Item 3. The multihead exposure apparatus according to Item 2.   2. The multi-head exposure apparatus according to claim 1, wherein the plurality of exposure heads are also arranged in a direction orthogonal to the continuous scanning direction within the exposure surface.   5. The multi-head exposure apparatus according to claim 1, wherein the plurality of exposure heads are also arranged in the continuous scanning direction. The plurality of exposure heads include:
6. The multi of claim 4, wherein each of the exposure areas of the plurality of exposure heads to the object to be exposed is arranged so as to cover the entire width of the object to be exposed that is orthogonal to the continuous scanning direction. Head exposure device. The plurality of exposure heads include:
The exposure heads are arranged so that each exposure region of the plurality of exposure heads to the object to be exposed partially covers the entire width of the object to be exposed perpendicular to the continuous scanning direction. 6. The multi-head exposure apparatus according to claim 5, wherein:   By changing the intensity of light emitted from each light modulation element of a two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, the exposure amount for a predetermined region is changed, and the exposure intensity is reduced. 8. The multi-head exposure apparatus according to claim 1, further comprising exposure intensity adjusting means for performing adjustment. A two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, and by inputting pattern data to each light modulation element of the two-dimensional spatial light modulation element, a desired region can be obtained In an exposure method in which a plurality of exposure heads capable of exposing the pattern in a batch are arranged, and exposure is performed while relatively continuously scanning the exposure head and the object to be exposed.
A direction perpendicular to at least the exposure surface of the object to be exposed so that each exposure region of the object to be exposed in the plurality of exposure heads covers the entire width of the object to be exposed perpendicular to the continuous scanning direction. An exposure method comprising: exposing the exposed object in the continuous scanning direction. A two-dimensional spatial light modulation element composed of a plurality of light modulation elements arranged two-dimensionally, and by inputting pattern data to each light modulation element of the two-dimensional spatial light modulation element, a desired region can be obtained In an exposure method in which a plurality of exposure heads capable of exposing the pattern in a batch are arranged, and exposure is performed while relatively continuously scanning the exposure head and the object to be exposed.
An exposure method comprising: arranging the plurality of exposure heads in at least the continuous scanning direction, and simultaneously exposing a plurality of objects to be exposed using the plurality of exposure heads arranged in the continuous scanning direction.   11. The exposure is continuously performed while the plurality of objects to be exposed are sequentially conveyed in the continuous scanning direction by a scanning unit that relatively scans the plurality of objects to be exposed. Exposure method.

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