JP4534651B2 - Exposure apparatus, device manufacturing method, and liquid recovery method - Google Patents

Description

The present invention relates to an exposure apparatus that exposes a substrate through a liquid, a device manufacturing method, and a liquid recovery method.

Semiconductor devices and liquid crystal display devices are manufactured by a so-called photolithography technique in which a pattern formed on a mask is transferred onto a photosensitive substrate. An exposure apparatus used in this photolithography process has a mask stage for supporting a mask and a substrate stage for supporting a substrate, and a mask pattern is transferred via a projection optical system while sequentially moving the mask stage and the substrate stage. It is transferred to the substrate. In recent years, in order to cope with higher integration of device patterns, higher resolution of the projection optical system is desired. The resolution of the projection optical system becomes higher as the exposure wavelength used is shorter and the numerical aperture of the projection optical system is larger. Therefore, the exposure wavelength used in the exposure apparatus is shortened year by year, and the numerical aperture of the projection optical system is also increasing. The mainstream exposure wavelength is 248 nm of the KrF excimer laser, but the 193 nm of the shorter wavelength ArF excimer laser is also being put into practical use. Also, when performing exposure, the depth of focus (DOF) is important as well as the resolution. The resolution R and the depth of focus δ are each expressed by the following equations.
R = k ₁ · λ / NA (1)
δ = ± k ₂ · λ / NA ² (2)
Here, λ is the exposure wavelength, NA is the numerical aperture of the projection optical system, and k ₁ and k ₂ are process coefficients. From the equations (1) and (2), it can be seen that the depth of focus δ becomes narrower when the exposure wavelength λ is shortened and the numerical aperture NA is increased in order to increase the resolution R.

If the depth of focus δ becomes too narrow, it becomes difficult to match the substrate surface with the image plane of the projection optical system, and the focus margin during the exposure operation may be insufficient. Therefore, as a method for substantially shortening the exposure wavelength and increasing the depth of focus, for example, a liquid immersion method disclosed in Patent Document 1 below has been proposed. In this immersion method, a space between the lower surface of the projection optical system and the substrate surface is filled with a liquid such as water or an organic solvent to form an immersion region, and the wavelength of exposure light in the liquid is 1 / n of that in air. (Where n is the refractive index of the liquid, which is usually about 1.2 to 1.6), the resolution is improved, and the depth of focus is expanded about n times.
International Publication No. 99/49504 Pamphlet

  By the way, as disclosed in Patent Document 1, the liquid in the immersion area formed on the substrate is recovered by the liquid recovery mechanism. However, since the photosensitive material is coated on the substrate, the liquid recovery is performed. The mechanism collects the liquid that has contacted the photosensitive material. In that case, if the liquid contains a substance generated from the substrate, the liquid contact surface of the liquid recovery mechanism may be affected by the liquid containing the substance, and the life of the apparatus may be deteriorated. is there.

  The present invention has been made in view of such circumstances, and provides an immersion exposure apparatus including a liquid recovery mechanism in which the influence received from the recovered liquid is suppressed, and a device manufacturing method using the exposure apparatus. With the goal.

  In order to solve the above-described problems, the present invention adopts the following configuration corresponding to FIGS. 1 to 7 shown in the embodiment. However, the reference numerals with parentheses attached to each element are merely examples of the element and do not limit each element.

  An exposure apparatus (EX) of the present invention is an exposure apparatus that exposes a substrate (P) through a liquid (LQ), and includes a liquid recovery mechanism (20, 40, 80) that recovers the liquid (LQ), and recovers the liquid. Among the mechanisms (20, 40, 80), at least a part of the liquid contact surface (23A, etc.) that contacts the recovered liquid (LQ) has corrosion resistance against the liquid (LQ). To do.

  In many cases, the photosensitive material coated on the substrate contains an acid, and when the liquid comes into contact with the photosensitive material, there is a possibility that the liquid contains an acid. When the liquid recovery mechanism recovers the liquid containing the acid, the liquid contact surface of the liquid recovery mechanism is likely to be corroded (rusted). According to the present invention, the liquid recovery mechanism is recovered from the liquid recovery mechanism. Since the liquid contact surface that comes into contact with the liquid has corrosion resistance to the liquid, corrosion due to the acid-containing liquid can be prevented. Therefore, the life of the apparatus can be improved.

  The exposure apparatus (EX) of the present invention is an exposure apparatus that exposes the substrate (P) through the liquid (LQ), and includes a liquid recovery mechanism (20, 40, 80) that recovers the liquid (LQ). The recovery mechanism (20, 40, 80) is characterized by having a removal device (29) for reducing or removing a predetermined substance contained in the recovered liquid (LQ).

  According to the present invention, since the predetermined substance contained in the recovered liquid can be reduced or removed by the removing device, even if a corrosive substance such as an acid is contained in the liquid, the substance is removed by the removing device. Can be removed. Therefore, the influence that the liquid recovery mechanism receives from the liquid containing the predetermined substance can be suppressed, and the life of the apparatus can be improved.

  The device manufacturing method of the present invention uses the above-described exposure apparatus (EX). According to the present invention, a device having a desired performance can be manufactured using an immersion exposure apparatus having a liquid recovery mechanism with an improved apparatus life.

  According to the present invention, it is possible to suppress the influence received from the recovered liquid and improve the life of the liquid recovery mechanism.

  Hereinafter, embodiments of the exposure apparatus of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram showing an embodiment of the exposure apparatus EX.

  In FIG. 1, an exposure apparatus EX includes a mask stage MST that can move while supporting a mask M, and a substrate holder PH that holds a substrate P, and a substrate stage that can move while holding the substrate P in the substrate holder PH. PST, illumination optical system IL for illuminating mask M supported on mask stage MST with exposure light EL, and substrate P supported on substrate stage PST for an image of the pattern of mask M illuminated with exposure light EL A projection optical system PL for performing projection exposure, and a control device CONT for controlling overall operation of the exposure apparatus EX. The control device CONT is connected to a storage device MRY that stores various types of information related to exposure processing. The control device CONT is connected to a notification device INF that notifies information related to exposure processing. The notification device INF includes a display device (display device), an alarm device that issues an alarm (warning) using sound or light, and the like.

  The exposure apparatus EX of the present embodiment is an immersion exposure apparatus to which an immersion method is applied in order to improve the resolution by substantially shortening the exposure wavelength and substantially increase the depth of focus. Is provided with an immersion mechanism 1 for forming an immersion area AR2 for the liquid LQ. The liquid immersion mechanism 1 includes a liquid supply mechanism 10 that supplies a liquid LQ onto the substrate P, a liquid recovery mechanism 20 that recovers the liquid LQ on the substrate P, and a nozzle disposed in the vicinity of the image plane side of the projection optical system PL. Member 70. The lower surface 70 </ b> A of the nozzle member 70 is provided with a liquid supply port 12 that forms part of the liquid supply mechanism 10 and a liquid recovery port 22 that forms part of the liquid recovery mechanism 20. Further, the exposure apparatus EX includes a measuring device 60 that measures the acidity of the liquid LQ recovered by the liquid recovery mechanism 20. The liquid supply mechanism 10 includes a functional liquid supply device 90 that can supply a functional liquid having a predetermined function different from the liquid LQ for forming the liquid immersion area AR2.

  In the present embodiment, pure water is used as the liquid LQ. The exposure apparatus EX transfers at least a part of the substrate P including the projection area AR1 of the projection optical system PL by the liquid LQ supplied from the liquid supply mechanism 10 while at least transferring the pattern image of the mask M onto the substrate P. A liquid immersion area AR2 that is larger than the projection area AR1 and smaller than the substrate P is locally formed. Specifically, the exposure apparatus EX uses the liquid immersion mechanism 1 to fill the liquid LQ between the optical element 2 at the image surface side tip of the projection optical system PL and the surface (exposed surface) of the substrate P. The substrate P is exposed by projecting the pattern image of the mask M onto the substrate P via the liquid LQ between the projection optical system PL and the substrate P and the projection optical system PL.

  Here, in the present embodiment, the pattern formed on the mask M is exposed to the substrate P while the mask M and the substrate P are synchronously moved in different directions (reverse directions) in the scanning direction (predetermined direction) as the exposure apparatus EX. An example of using a scanning exposure apparatus (so-called scanning stepper) will be described. In the following description, the synchronous movement direction (scanning direction, predetermined direction) of the mask M and the substrate P in the horizontal plane is the X axis direction, and the direction orthogonal to the X axis direction is the Y axis direction (non-scanning direction) in the horizontal plane. A direction perpendicular to the X-axis and Y-axis directions and coincident with the optical axis AX of the projection optical system PL is defined as a Z-axis direction. In addition, the rotation (inclination) directions around the X axis, the Y axis, and the Z axis are the θX, θY, and θZ directions, respectively. Here, the “substrate” includes a substrate in which a photosensitive material (resist) is coated on a base material such as a semiconductor wafer, and the “mask” includes a reticle on which a device pattern to be reduced and projected on the substrate is formed.

The illumination optical system IL illuminates the mask M supported by the mask stage MST with the exposure light EL, and the exposure light source, an optical integrator that equalizes the illuminance of the light beam emitted from the exposure light source, and an optical integrator A condenser lens for condensing the exposure light EL from the light source, a relay lens system, a field stop for setting an illumination area on the mask M by the exposure light EL, and the like. A predetermined illumination area on the mask M is illuminated with the exposure light EL having a uniform illuminance distribution by the illumination optical system IL. As the exposure light EL emitted from the illumination optical system IL, for example, far ultraviolet light (g-line, h-line, i-line) and KrF excimer laser light (wavelength 248 nm) emitted from a mercury lamp, DUV light), vacuum ultraviolet light (VUV light) such as ArF excimer laser light (wavelength 193 nm) and F ₂ laser light (wavelength 157 nm), or the like is used. In this embodiment, ArF excimer laser light is used. As described above, the liquid LQ in the present embodiment is pure water and can be transmitted even if the exposure light EL is ArF excimer laser light. Further, pure water can transmit ultraviolet rays (g-rays, h-rays, i-rays) and far-ultraviolet light (DUV light) such as KrF excimer laser light (wavelength 248 nm).

  The mask stage MST can move while holding the mask M, can move two-dimensionally in a plane perpendicular to the optical axis AX of the projection optical system PL, that is, in the XY plane, and can be rotated slightly in the θZ direction. The mask stage MST is driven by a mask stage driving device MSTD including a linear motor and the like. The mask stage driving device MSTD is controlled by the control device CONT. A movable mirror 31 is provided on the mask stage MST. A laser interferometer 32 is provided at a position facing the moving mirror 31. The two-dimensional position and rotation angle of the mask M on the mask stage MST are measured in real time by the laser interferometer 32, and the measurement result is output to the control device CONT. The control device CONT drives the mask stage driving device MSTD based on the measurement result of the laser interferometer 32, thereby positioning the mask M supported on the mask stage MST.

  The projection optical system PL projects and exposes the pattern of the mask M onto the substrate P at a predetermined projection magnification β, and includes a plurality of optical elements including an optical element (lens) 2 provided at the front end portion on the substrate P side. These optical elements are supported by a lens barrel PK. In the present embodiment, the projection optical system PL is a reduction system having a projection magnification β of, for example, 1/4, 1/5, or 1/8. Note that the projection optical system PL may be either an equal magnification system or an enlargement system. The optical element 2 at the tip of the projection optical system PL is exposed from the lens barrel PK, and the liquid LQ in the liquid immersion area AR2 is in contact with the optical element 2.

  The substrate stage PST includes a Z stage 52 that holds the substrate P via a substrate holder PH, and an XY stage 53 that supports the Z stage 52. The XY stage 53 is supported on the base BP. The substrate stage PST is driven by a substrate stage driving device PSTD that includes a linear motor or the like. The substrate stage driving device PSTD is controlled by the control device CONT. The Z stage 52 can move the substrate P held by the substrate holder PH in the Z-axis direction and in the θX and θY directions (inclination directions). The XY stage 53 can move the substrate P held by the substrate holder PH in the XY direction (direction substantially parallel to the image plane of the projection optical system PL) and the θZ direction via the Z stage 52. Needless to say, the Z stage and the XY stage may be provided integrally.

  A recess 50 is provided on the Z stage 52 (substrate stage PST), and the substrate holder PH is disposed in the recess 50. The Z stage 52 has an upper surface 51 disposed around the substrate P held by the substrate holder PH. The upper surface 51 of the Z stage 52 (substrate stage PST) is a flat surface that is substantially the same height (level) as the surface of the substrate P held by the substrate holder PH. There is a gap of about 0.1 to 1 mm between the edge portion of the substrate P and the upper surface 51 provided around the substrate P, but the liquid LQ almost never flows into the gap due to the surface tension of the liquid LQ. Absent.

  A movable mirror 33 is provided on the side surface of the Z stage 52 (substrate stage PST). A laser interferometer 34 is provided at a position facing the movable mirror 33. The two-dimensional position and rotation angle of the substrate P on the substrate stage PST are measured in real time by the laser interferometer 34, and the measurement result is output to the control device CONT. Based on the measurement result of the laser interferometer 34, the control device CONT holds the substrate holder PH by driving the XY stage 53 via the substrate stage driving device PSTD in the two-dimensional coordinate system defined by the laser interferometer 34. The substrate P is positioned in the X-axis direction and the Y-axis direction.

  Although not shown, the exposure apparatus EX includes an oblique incidence type focus detection system as disclosed in, for example, Japanese Patent Laid-Open No. 8-37149. The focus detection system detects surface position information of the surface of the substrate P, and the position (focus position) in the Z-axis direction of the surface of the substrate P with respect to the image plane via the projection optical system PL and the liquid LQ, and The attitude of the substrate P in the tilt direction (θX, θY direction) is obtained. The control device CONT drives the Z stage 52 of the substrate stage PST via the substrate stage driving device PSTD, so that the position (focus position) of the substrate P held by the Z stage 52 in the Z-axis direction, and θX, θY Control position in direction. The Z stage 52 operates based on a command from the control device CONT based on the detection result of the focus detection system, and controls the focus position (Z position) and the tilt angle of the substrate P to control the surface (exposure surface) of the substrate P. It is adjusted to the image plane formed via the projection optical system PL and the liquid LQ.

  Next, the liquid immersion mechanism 1 will be described with reference to FIG. The liquid supply mechanism 10 of the liquid immersion mechanism 1 is for supplying a predetermined liquid LQ to the image plane side of the projection optical system PL, and includes a liquid supply unit 11 capable of delivering the liquid LQ, and the liquid supply unit 11. And a supply pipe 13 for connecting one end thereof. The other end of the supply pipe 13 is connected to the nozzle member 70. The liquid supply unit 11 includes a tank that stores the liquid LQ, a pressure pump, a filter unit that removes bubbles and foreign matters contained in the liquid LQ, a temperature control device that adjusts the temperature of the supplied liquid LQ, and the like. Moreover, in this embodiment, the liquid supply part 11 is comprised including the pure water manufacturing apparatus.

  The liquid recovery mechanism 20 is for recovering the liquid LQ on the image plane side of the projection optical system PL, and includes a vacuum system 26 and a recovery tube 23 that connects one end of the vacuum system 26. . The other end of the recovery pipe 23 is connected to the nozzle member 70. As a vacuum system, a vacuum system in a factory where the exposure apparatus EX is disposed may be used without providing a vacuum pump or the like in the exposure apparatus EX. A gas-liquid separator 25 is provided in the middle of the recovery pipe 23, and the liquid recovery unit 21 is connected to the gas-liquid separator 25 via a second recovery pipe 27. The liquid recovery unit 21 includes a tank or the like that stores the recovered liquid LQ.

  The nozzle member 70 is an annular member provided so as to surround the side surface of the optical element 2 above the substrate P (substrate stage PST). A gap is provided between the nozzle member 70 and the optical element 2, and the nozzle member 70 is supported by a predetermined support mechanism so as to be vibrationally separated from the optical element 2. The lower surface 70A of the nozzle member 70 faces the surface of the substrate P (the upper surface 51 of the substrate stage PST).

  The lower surface 70A of the nozzle member 70 is provided with a liquid supply port 12 for supplying the liquid LQ onto the substrate P (on the substrate stage PST). A plurality of liquid supply ports 12 are provided on the lower surface 70 </ b> A of the nozzle member 70. A supply flow path 14 that connects the supply pipe 13 and each of the liquid supply ports 12 is formed inside the nozzle member 70. One end of the supply flow path 14 is connected to the other end of the supply pipe 13 via a joint 13T, and the other end is branched from the middle so as to be connected to each of the plurality of liquid supply ports 12. .

  Further, the lower surface 70A of the nozzle member 70 is provided with a liquid recovery port 22 for recovering the liquid LQ on the substrate P (on the substrate stage PST). The liquid recovery port 22 is annularly provided on the outer side with respect to the optical element 2 so as to surround the plurality of liquid supply ports 12 on the lower surface 70 </ b> A of the nozzle member 70. The liquid recovery port 22 is provided with a porous body 22P. In addition, a recovery flow path 24 that connects the recovery pipe 23 and the liquid recovery port 22 is formed inside the nozzle member 70. One end of the recovery flow path 24 is connected to the other end of the recovery pipe 23 via a joint 23T, and the other end is formed to correspond to the annular liquid recovery port 22. That is, the recovery flow path 24 is an annular flow path 24K formed in an annular shape so as to correspond to the liquid recovery port 22, and a manifold flow path that connects a part of the annular flow path 24K and the other end of the recovery pipe 23. 24M.

  The operations of the liquid supply mechanism 10 and the liquid recovery mechanism 20 are controlled by the control device CONT. When supplying the liquid LQ onto the substrate P, the control device CONT drives the liquid supply unit 11 of the liquid supply mechanism 10 to send out the liquid LQ, and passes through the supply pipe 13 and the supply flow path 14 of the nozzle member 70. Then, the liquid LQ is supplied onto the substrate P from the liquid supply port 12 provided above the substrate P. Here, as described above, the liquid supply unit 11 includes a pure water manufacturing apparatus, and supplies the liquid LQ cleaned by the pure water manufacturing apparatus onto the substrate P. The pure water manufacturing apparatus cleans the liquid LQ returned from, for example, tap water or the liquid recovery mechanism 20. In addition, as a pure water manufacturing apparatus, you may make it use the pure water manufacturing apparatus of the factory in which the exposure apparatus EX is arrange | positioned, without providing the pure water manufacturing apparatus in the exposure apparatus EX.

  Further, when recovering the liquid LQ on the substrate P, the control device CONT drives the vacuum system 26 of the liquid recovery mechanism 20. When the vacuum system 26 is driven, the liquid LQ on the substrate P is recovered through the liquid recovery port 22 and flows through the recovery flow path 24 and the recovery pipe 23. A gas-liquid separator 25 is provided in the middle of the recovery tube 23, the gas component separated by the gas-liquid separator 25 is sucked into the vacuum system 26, and the liquid component is recovered through the second recovery tube 27. Collected by the unit 21. Thus, the provision of the gas-liquid separator 25 can prevent the inconvenience of the liquid component flowing into the vacuum system 26. Further, the liquid LQ recovered by the liquid recovery unit 21 is discarded, for example, via the pipe 28 or returned to the liquid supply mechanism 10 (the pure water production apparatus of the liquid supply unit 11) and reused. In the present embodiment, the liquid recovery part 21 of the liquid recovery mechanism 20 and the liquid supply part 11 of the liquid supply mechanism 10 are connected by a pipe 28, and the liquid LQ recovered by the liquid recovery part 21 passes through the pipe 28. It flows and returns to the pure water manufacturing apparatus of the liquid supply part 11.

  Meanwhile, the liquid recovery mechanism 20 recovers the liquid LQ that has come into contact with the substrate P through the liquid recovery port 22 of the nozzle member 70. However, as shown in FIG. The photosensitive material Pg is covered. Therefore, the liquid recovery mechanism 20 recovers the liquid LQ that has contacted the photosensitive material Pg. When the liquid LQ and the photosensitive material Pg come into contact with each other, a part of the photosensitive material Pg may be eluted in the liquid LQ. Since the photosensitive material Pg contains acids such as sulfuric acid and carboxylic acid, there is a possibility that the liquid LQ and the photosensitive material Pg come into contact with each other, so that the liquid LQ may contain an acid. Therefore, when the liquid LQ containing acid comes into contact with the substrate P and is recovered by the liquid recovery mechanism 20, the liquid that contacts the recovered liquid LQ, such as the inner wall surface of the recovery tube 23, of the liquid recovery mechanism 20. Contact surfaces can be corroded by acid.

  In the present embodiment, as shown in FIG. 3, the recovery tube 23 having the inner wall surface 23A that contacts the liquid LQ that contacts the substrate P is formed of a material S that has corrosion resistance against the liquid LQ. . Examples of the material S having corrosion resistance include fluorine-based resins such as polytetrafluoroethylene (Teflon (registered trademark)), stainless steel, and the like. Specifically, the recovery pipe 23 can be constituted by, for example, a fluorine resin tube or a stainless steel pipe member. By forming the recovery pipe 23 with the material S containing fluorine-based resin or stainless steel, the recovery pipe 23 is corroded or rusted even if the liquid LQ containing acid contacts the inner wall surface 23A of the recovery pipe 23. Can prevent inconvenience. Therefore, the corrosion resistance of the recovery pipe 23 can be improved and the life can be extended.

  Alternatively, as shown in FIG. 4, the material S may be coated on the inner wall surface 23 </ b> A ′ of the base material constituting the recovery pipe 23. This also prevents the inconvenience that the recovery pipe 23 corrodes.

  Returning to FIG. 2, a measuring device 60 capable of measuring the acidity of the liquid LQ is connected to the branch pipe 23 </ b> K branched from the middle of the recovery pipe 23. The measuring device 60 includes, for example, a pH (pH) monitor. The liquid LQ recovered from the liquid recovery port 22 flows through the recovery pipe 23, and most of the liquid LQ is recovered by the liquid recovery part 21, but the remaining part flows into the measuring device 60 via the branch pipe 23K. The measuring device 60 measures the acidity of the liquid LQ recovered from the liquid recovery port 22 and flowing through the recovery pipe 23 and the branch pipe 23K.

  In the present embodiment, the measuring device 60 measures the acidity of the liquid LQ flowing through the branch pipe 23K branched from the middle of the recovery pipe 23. By adopting such measurement, since the liquid LQ is constantly supplied to the measuring device 60, the measuring device 60 can always measure the acidity of the liquid LQ during and before and after exposure. ing. That is, the measuring device 60 can measure the liquid LQ in parallel with the immersion exposure operation for the substrate P. The measurement result of the measuring device 60 is output to the control device CONT. The control device CONT can always monitor the acidity of the liquid LQ recovered from the substrate P via the liquid recovery port 22 based on the measurement result of the measuring device 60. The measurement result of the measuring device 60 is notified (displayed) by the notification device INF. Note that the installation position of the measuring device 60 may be, for example, in the vicinity of the liquid recovery port 22.

  The functional liquid supply device 90 supplies a functional liquid LK having a predetermined function different from the liquid LQ for forming the liquid immersion area AR2, and is connected to the liquid supply unit 11 via the supply pipe 15. Has been. In the present embodiment, the functional liquid supply device 90 supplies an alkaline liquid (functional liquid) LK having a function capable of adjusting (neutralizing) the acidity (pH) of the inner wall of the piping system through which the liquid LQ flows. To do. The supply pipe 15 is provided with a valve 15B that opens and closes the flow path of the supply pipe 15. The control device CONT controls the operation of the functional liquid supply device 90 based on the measurement result of the measurement device 60.

  Next, a procedure for exposing the substrate P using the exposure apparatus EX having the above-described configuration will be described.

  When the substrate P to be exposed is loaded onto the substrate stage PST, the controller CONT drives the liquid immersion mechanism 1 to form the liquid immersion area AR2 of the liquid LQ on the substrate P. The control device CONT illuminates the mask M with the exposure light EL using the illumination optical system IL, and forms a pattern image of the mask M illuminated with the exposure light EL on the substrate P via the projection optical system PL and the liquid LQ. .

  The liquid LQ recovered through the liquid recovery port 22 flows through the recovery pipe 23. As described with reference to FIG. 3 and FIG. 4, the inner wall surface 23A of the recovery pipe 23 that contacts the liquid LQ is liquid. Since it is formed of the material S having corrosion resistance to LQ, the recovery pipe 23 can be prevented from corroding even when the liquid LQ contains an acid.

  Further, in the piping system constituting the liquid recovery mechanism 20, in addition to the recovery pipe 23, the branch pipe 23 </ b> K and the second recovery pipe 27 are formed of the material S, or inside the branch pipe 23 </ b> K and the second recovery pipe 27 The wall surface can be coated with the material S. Alternatively, the pipe 28 connecting the liquid recovery mechanism 20 and the liquid recovery mechanism 10 can be formed of the material S, or the inner wall surface thereof can be covered with the material S.

  In the present embodiment, the substrate stage PST has a flat surface (upper surface) 51 that is substantially flush with the surface of the substrate P around the substrate P held by the substrate stage PST (substrate holder PH). Yes. The lower surface 70A of the nozzle member 70 and the lower surface 2A of the optical element 2 are substantially flat surfaces, and the lower surface 70A of the nozzle member 70 and the lower surface 2A of the optical element 2 are substantially flush with each other. Thereby, the liquid immersion area AR2 can be satisfactorily formed within a desired range between the lower surface 70A of the nozzle member 70 and the lower surface 2A of the optical element 2 and the substrate P (substrate stage PST). The liquid LQ in contact with the substrate P also contacts the lower surface 70A of the nozzle member 70, the upper surface 51 of the substrate stage PST, or the inner wall surface of the recovery flow path 24 connected to the liquid recovery port 22 in the nozzle member 70. However, the nozzle member 70 is made of stainless steel, or the upper surface 51 of the substrate stage PST is coated with a fluorine-based resin, so that the lower surface 70A of the nozzle member 70, the inner wall surface of the recovery flow path 24, the substrate stage PST. The upper surface 51 can also be made resistant to the liquid LQ. In this embodiment, the lower surface 70A of the nozzle member 70A is a flat surface and is substantially flush with the lower surface 2A of the optical element 2. However, if the liquid immersion area AR2 can be formed well, the lower surface 70A of the nozzle member 70 is formed. A step may exist, or a step may exist between the lower surface 70A of the nozzle member 70 and the lower surface 2A of the optical element 2.

  In the liquid recovery mechanism 20, the process for coating the material S on the liquid contact surface in contact with the liquid LQ as described above includes, for example, a process of applying the material S to the liquid contact surface, or the material S. The process etc. which stick a thin film are mentioned.

  As described above, the liquid contact surface of the liquid recovery mechanism 20 that is in contact with the recovered liquid LQ is resistant to the liquid LQ, thereby preventing corrosion due to the acid L-containing liquid LQ. The device life can be improved.

  In the embodiment described above, the liquid contact surface of the liquid recovery mechanism 20 is formed of the material S. However, the liquid contact surface of the liquid supply mechanism 10 may be formed of the material S.

  In the above-described embodiment, it has been described that the acid is eluted from the photosensitive material Pg into the liquid LQ. However, substances other than the acid described above (for example, amine-based substances) may be eluted into the liquid. The substance may affect the liquid contact surface of the liquid recovery mechanism 20. In such a case, the material S forming the liquid contact surface of the liquid recovery mechanism 20 may be appropriately selected according to the photosensitive material Pg (in accordance with the material eluted from the photosensitive material Pg into the liquid LQ).

  In the above-described embodiment, a film (topcoat film) made of a material different from the photosensitive material Pg is provided so as to further cover the photosensitive material Pg coated on the substrate Pb, and the photosensitive material Pg and the liquid LQ are provided. You may make it prevent contact of. In such a case, the material S that forms the liquid contact surface of the liquid recovery mechanism 20 may be appropriately selected according to the topcoat film.

  In the above-described embodiment, the liquid contact surface of the liquid recovery mechanism 20 that recovers the liquid LQ from above the substrate P is made corrosion resistant to the liquid LQ. However, as shown in FIG. The liquid contact surfaces of the second and third liquid recovery mechanisms 40 and 80 that recover the liquid LQ may be made corrosion resistant to the liquid LQ. Here, like the liquid recovery mechanism 20, the second and third liquid recovery mechanisms 40 and 80 recover the liquid LQ in contact with the substrate P.

  In FIG. 5, the substrate holder PH includes a base material 49, a peripheral wall portion 42 provided on the base material 49, and having an upper surface 42 </ b> A formed in an annular shape so as to face the edge region of the back surface Pc of the substrate P; The support part 43 which consists of several pin-shaped members arrange | positioned inside the surrounding wall part 42 on the base material 49 is provided. In addition, a plurality of suction ports 44 for sucking the gas in the space 41 surrounded by the base material 49, the peripheral wall portion 42, and the substrate P are provided on the base material 49 inside the peripheral wall portion 42. Each of the suction ports 44 is connected to a vacuum system 46 through a flow path 48. When the vacuum system 46 is driven, the gas in the space 41 is sucked through the suction port 44, and the space 41 is made negative pressure, whereby the substrate P is sucked and held on the support portion 43. That is, the substrate holder PH has a so-called pin chuck mechanism.

  The second liquid recovery mechanism 40 includes the vacuum system 46 connected to the suction port 44 via the flow path 48, a gas-liquid separator 45 provided in the middle of the flow path 45, and a gas-liquid separator 45. And a liquid recovery unit 47 connected to the.

  For example, when immersion exposure is performed on an edge area on the substrate P, the immersion area AR2 of the liquid LQ is formed between the edge portion of the surface of the substrate P held by the substrate holder PH and the surrounding substrate stage PST (Z stage 52). There is a case where it is arranged on a gap A formed between the upper surface 51 and the upper surface 51. In that case, there is a possibility that the liquid LQ that has entered from the gap A flows around to the back surface Pc side of the substrate P through the gap between the back surface Pc of the substrate P and the upper surface 42A of the peripheral wall portion 42. The second liquid recovery mechanism 40 enters the gap A and recovers the liquid LQ that has entered the back surface Pc side of the substrate P. The liquid LQ that has entered the back surface side of the substrate P 44, and flows through the flow path 48 and flows into the gas-liquid separator 45. The gas component separated by the gas-liquid separator 45 is sucked into the vacuum system 46 and the liquid component is recovered by the liquid recovery unit 47.

  In the embodiment shown in FIG. 5, the inner wall surface 56 inside the recess 50 of the substrate stage PST that contacts the liquid LQ that contacts the substrate P, the upper surface 42A of the peripheral wall portion 42, the surface of the support portion 43, the base The upper surface of the material 49, the vicinity of the suction port 44, the inner wall surface of the flow channel 48, and the like have corrosion resistance against the liquid LQ.

  In FIG. 5, a holding member 81 for holding the liquid LQ that flows out from the upper surface 51 of the substrate stage PST is provided on the side surface of the substrate stage PST (Z stage 52). The holding member 81 is a flange member formed so as to surround the Z stage 52. A suction port 84 is formed in the holding member 81, and a vacuum system 86 is connected to the suction port 84 through a flow path 88.

  The third liquid recovery mechanism 80 includes the holding member 81, a vacuum system 86 connected to the suction port 84 formed in the holding member 81 via a flow path 88, and a gas-liquid separation provided in the middle of the flow path 88. And a liquid recovery part 87 connected to the gas-liquid separator 85, and recovers the liquid LQ flowing out of the substrate stage PST. The liquid LQ that flows out of the substrate stage PST and is collected by the holding member 81 by the gravitational action is recovered through the suction port 84 by driving the vacuum system 86. The liquid LQ recovered via the suction port 84 flows through the flow path 88 and flows into the gas-liquid separator 85. The gas component separated by the gas-liquid separator 85 is sucked into the vacuum system 86 and the liquid component is recovered by the liquid recovery unit 87.

  In the embodiment shown in FIG. 5, the upper surface 51 of the substrate stage PST that contacts the liquid LQ, the liquid contact surface including the vicinity of the suction port 84 of the holding member 81, the inner wall surface of the flow path 88, etc. Corrosion resistance.

  Incidentally, as described above, the exposure apparatus EX includes the measurement device 60 that measures the acidity of the liquid LQ recovered through the liquid recovery port 22, and the measurement device 60 is used during exposure of the substrate P and exposure. The acidity of the liquid LQ can always be monitored before and after. Therefore, when the measurement value of the measurement device 60 becomes equal to or greater than a predetermined allowable value, the control device CONT stops the supply of the liquid LQ for immersion exposure by the liquid supply mechanism 10 and drives the valve 28B. Then, the flow path of the pipe 28 is closed, and the valve 15B is driven to open the flow path of the supply pipe 15, and the functional liquid LK is supplied from the functional liquid supply device 90. The information regarding the allowable value is stored in advance in the storage device MRY, and the control device CONT is based on the measurement result of the measuring device 60 and the information regarding the allowable value stored in the storage device MRY. 90 is controlled.

  In this embodiment, in order to reduce and neutralize the acidity of the contact surface with the liquid LQ of the liquid recovery mechanism 20, such as the inner wall surface 23A of the recovery pipe 23, the functional liquid supply device 90 is made of an alkaline liquid. Supply the functional fluid LK.

  In order to supply the functional liquid LK, the control device CONT opens a flow path of the supply pipe 15 by driving a valve 15B provided in the supply pipe 15 that connects the functional liquid supply apparatus 90 and the liquid supply section 11. The flow path of the pipe 28 is closed using the valve 28B. By doing so, the functional liquid LK is supplied from the functional liquid supply device 90 to the liquid supply unit 11. The functional liquid LK supplied from the functional liquid supply device 90 is supplied to the supply pipe 13 via the liquid supply unit 11, flows through the supply flow path 14 of the nozzle member 70, and then is projected from the liquid supply port 12 to the projection optical system PL. Is supplied to the image plane side.

  When the functional liquid supply device 90 supplies the functional liquid LK to the image plane side of the projection optical system PL, it is preferable to hold a dummy substrate on the substrate stage PST (substrate holder PH). The dummy substrate has substantially the same size and shape as the substrate P for device manufacture. The functional liquid LK delivered from the functional liquid supply device 90 is supplied onto the dummy substrate from the liquid supply port 12, and forms an immersion area on the image plane side of the projection optical system PL. Further, when the functional liquid LK is supplied from the functional liquid supply device 90, the liquid recovery mechanism 20 performs the liquid recovery operation as in the liquid immersion exposure operation. Accordingly, the functional liquid LK in the liquid immersion area formed on the image plane side of the projection optical system PL is recovered through the liquid recovery port 22 and flows through the recovery flow path 24, the recovery pipe 23, and the second recovery pipe 27. Thereafter, the liquid is recovered by the liquid recovery unit 21. When the functional liquid LK flows through the recovery flow path 24 and the recovery pipe 23, the acidity of the inner wall surface 23A of the recovery pipe 23 can be adjusted (neutralized). Therefore, the corrosion of the recovery pipe 23 caused by the acid can be further reliably prevented. Further, when the immersion area of the functional liquid LK is formed, the substrate stage PST is moved in the XY direction, and the functional liquid LK is brought into contact with the upper surface 51 of the substrate stage PST, whereby the acidity of the upper surface 51 is also increased. It can be adjusted (neutralized). Further, when the functional liquid LK and the lower surface 70A of the nozzle member 70 are in contact with each other, the acidity of the lower surface 70A can be adjusted (neutralized). In the above-described embodiment, since the liquid immersion area forming operation of the functional liquid LK is performed in the same procedure as the liquid immersion exposure operation, the acidity of the liquid contact surface of the liquid recovery mechanism 20 is efficiently adjusted. can do.

  Moreover, after the neutralization process by flowing the functional liquid LK is completed, the liquid LQ is measured using the measuring device 60, so that it can be confirmed whether or not the neutralization process has been performed satisfactorily.

  In the above-described embodiment, the neutralization process is performed by controlling the operation of the liquid supply mechanism 10 including the functional liquid supply device 90 based on the measurement result of the measurement device 60. Of course, the neutralization process may be performed at predetermined time intervals (for example, every month, every year) regardless of the measurement result.

  Further, when the measurement value of the measurement device 60 exceeds a predetermined allowable value, the control device CONT may notify the notification device INF to that effect. By the notification of the notification device INF, the operator can perform, for example, a neutralization operation of the piping system including the recovery pipe 23 or a replacement operation of the piping system.

  In the above-described embodiment, the process (neutralization process) for flowing the functional liquid LK and the immersion exposure process are performed separately, but the functional liquid LK can be used as a liquid for immersion exposure. If so, the liquid immersion area AR2 for liquid immersion exposure may be formed of the functional liquid LK. In this case, the neutralization process and the immersion exposure process are performed together.

  In the above-described embodiment, the functional liquid supply device 90 is configured to flow the functional liquid LK also to the liquid supply unit 11, but the middle of the supply pipe 13 and the functional liquid supply device 90 are connected, and the connection unit Alternatively, the functional liquid LK may be supplied downstream.

  FIG. 6 is a diagram showing another embodiment. In the following description, the same or equivalent components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof is simplified or omitted.

  In FIG. 6, the liquid recovery mechanism 20 includes a filter member 29 that constitutes a removal device that reduces or removes a predetermined substance contained in the recovered liquid LQ. The filter member 29 is provided at a predetermined position in the flow path through which the liquid LQ recovered from the liquid recovery port 22 flows. In the embodiment of FIG. 6, the filter member 29 is provided in the middle of the recovery pipe 23 through which the liquid LQ recovered from the liquid recovery port 22 flows. It may be provided in the vicinity of the recovery port 22.

  As described above, the liquid LQ in contact with the substrate P (photosensitive material Pg) may contain an acid, but the filter member 29 can remove the acid contained in the liquid LQ (capturing). (Collectable) chemical filter. Thereby, even if a corrosive substance such as an acid is contained in the recovered liquid LQ, the substance can be removed. Therefore, the piping system including the recovery pipe 23 and the second recovery pipe 27 on the downstream side of the filter member 29 is not affected by the acid. Since the acid in the liquid LQ can be removed or reduced by the filter member 29, the liquid contact surface of the piping system downstream of the filter member 29 does not have to be formed of the material S having corrosion resistance. The degree of freedom of selection of materials that can be used as the piping system is increased, resulting in an increase in the degree of design freedom in designing the apparatus, and a reduction in apparatus cost. Moreover, since the influence which the liquid LQ containing an acid has with respect to the liquid recovery mechanism 20 can be suppressed, the lifetime of the liquid recovery mechanism 20 can be improved. Therefore, inconveniences such as frequent replacement of the piping system due to corrosion (rust) or the like can be prevented.

  As described above, when the liquid LQ recovered by the liquid recovery mechanism 20 (liquid recovery unit 21) is returned to the liquid supply mechanism 10 (liquid supply unit 11) via the pipe 29, the acidity is lowered by the filter member 29. The liquid LQ thus made can be returned to the liquid supply mechanism 10. Therefore, in the liquid supply mechanism 10, when the liquid LQ returned from the liquid recovery mechanism 20 is cleaned and reused, the processing load for cleaning is reduced.

  In the present embodiment, the branch pipe 23 </ b> K of the collection pipe 23 is provided on the downstream side of the filter member 29. That is, the measuring device 60 measures the acidity of the liquid LQ that has passed through the filter member 29. Therefore, based on the measurement result of the measuring device 60, the control device CONT can determine the performance of the filter member 29 and the deterioration over time. That is, when the performance of the filter member 29 (performance for removing acid) is low, or when the filter member 29 deteriorates with time, the acid contained in the liquid LQ recovered from the liquid recovery port 22 is not sufficiently removed. . Therefore, the control device CONT can determine the performance of the filter member 29 and the deterioration over time based on the measurement result when the liquid LQ that has passed through the filter member 29 is measured by the measuring device 60. Then, the control device CONT notifies the measurement result of the measurement device 60 by the notification device INF, or notifies that the filter member 29 has deteriorated based on the measurement result of the measurement device 60 or prompts replacement of the filter member 29. Notification can be made with the device INF. Thereby, for example, the operator can replace the filter member 29 with a new one based on the notification result of the notification device INF.

  Further, by storing the measurement value of the measuring device 60, the replacement period of the filter member 29, and the like as log information in the storage device MRY, the control device CONT uses the notification device INF, for example, based on the log information. The replacement time of the filter member 29 can be notified.

  Of course, it is possible to provide the filter member 29 at a predetermined position of the flow path through which the liquid LQ flows in the second and third liquid recovery mechanisms 40 and 80 described with reference to FIG.

  As described above, the liquid LQ in the present embodiment is composed of pure water. Pure water has an advantage that it can be easily obtained in large quantities at a semiconductor manufacturing factory or the like, and has no adverse effect on the photoresist, optical element (lens), etc. on the substrate P. In addition, pure water has no adverse effects on the environment, and since the impurity content is extremely low, it can be expected to clean the surface of the substrate P and the surface of the optical element provided on the front end surface of the projection optical system PL. . When the purity of pure water supplied from a factory or the like is low, the exposure apparatus may have an ultrapure water production device.

  The refractive index n of pure water (water) with respect to the exposure light EL having a wavelength of about 193 nm is said to be approximately 1.44. When ArF excimer laser light (wavelength 193 nm) is used as the light source of the exposure light EL, On the substrate P, the wavelength is shortened to 1 / n, that is, about 134 nm, and a high resolution can be obtained. Furthermore, since the depth of focus is enlarged by about n times, that is, about 1.44 times compared with that in the air, the projection optical system PL can be used when it is sufficient to ensure the same depth of focus as that in the air. The numerical aperture can be further increased, and the resolution is improved in this respect as well.

  As described above, when the liquid immersion method is used, the numerical aperture NA of the projection optical system may be 0.9 to 1.3. When the numerical aperture NA of the projection optical system becomes large in this way, the imaging performance may deteriorate due to the polarization effect with random polarized light conventionally used as exposure light. desirable. In that case, linearly polarized illumination is performed in accordance with the longitudinal direction of the line pattern of the mask (reticle) line-and-space pattern. From the mask (reticle) pattern, the S-polarized light component (TE-polarized light component), that is, the line pattern It is preferable that a large amount of diffracted light having a polarization direction component is emitted along the longitudinal direction. When the space between the projection optical system PL and the resist applied on the surface of the substrate P is filled with a liquid, the space between the projection optical system PL and the resist applied on the surface of the substrate P is filled with air (gas). Compared with the case where the transmittance of the diffracted light of the S-polarized component (TE-polarized component) contributing to the improvement of the contrast is high on the resist surface, the numerical aperture NA of the projection optical system exceeds 1.0. Even in this case, high imaging performance can be obtained. Further, it is more effective to appropriately combine a phase shift mask or an oblique incidence illumination method (particularly a die ball illumination method) or the like according to the longitudinal direction of the line pattern as disclosed in JP-A-6-188169. In particular, the combination of the linearly polarized illumination method and the diball illumination method is used when the periodic direction of the line-and-space pattern is limited to a predetermined direction, or when the hole pattern is closely packed along the predetermined direction. It is effective when For example, when illuminating a halftone phase shift mask (pattern having a half pitch of about 45 nm) with a transmittance of 6% by using both the linearly polarized illumination method and the dieball illumination method, a diball is formed on the pupil plane of the illumination system. If the illumination σ defined by the circumscribed circle of the two luminous fluxes is 0.95, the radius of each luminous flux on the pupil plane is 0.125σ, and the numerical aperture of the projection optical system PL is NA = 1.2, the randomly polarized light is The depth of focus (DOF) can be increased by about 150 nm rather than using it.

  Further, for example, an ArF excimer laser is used as the exposure light, and a fine line and space pattern (for example, a line and space of about 25 to 50 nm) is formed on the substrate by using the projection optical system PL with a reduction magnification of about 1/4. When exposing on P, depending on the structure of the mask M (for example, the fineness of the pattern and the thickness of chrome), the mask M acts as a polarizing plate due to the Wave guide effect, and the P-polarized component (TM polarized light) that lowers the contrast. More diffracted light of the S-polarized component (TE polarized component) is emitted from the mask M than the diffracted light of the component. In this case, it is desirable to use the above-mentioned linearly polarized illumination, but even if the mask M is illuminated with random polarized light, it is high even when the numerical aperture NA of the projection optical system PL is as large as 0.9 to 1.3. Resolution performance can be obtained.

  When an extremely fine line-and-space pattern on the mask M is exposed on the substrate P, the P-polarized component (TM-polarized component) is larger than the S-polarized component (TE-polarized component) due to the Wire Grid effect. For example, an ArF excimer laser is used as exposure light, and a line and space pattern larger than 25 nm is exposed on the substrate P using the projection optical system PL with a reduction magnification of about 1/4. In this case, since the diffracted light of the S polarization component (TE polarization component) is emitted from the mask M more than the diffracted light of the P polarization component (TM polarization component), the numerical aperture NA of the projection optical system PL is 0.9. High resolution performance can be obtained even when the value is as large as -1.3.

  Furthermore, not only linearly polarized illumination (S-polarized illumination) matched to the longitudinal direction of the line pattern of the mask (reticle) but also a circle centered on the optical axis as disclosed in JP-A-6-53120. A combination of the polarization illumination method that linearly polarizes in the tangential (circumferential) direction and the oblique incidence illumination method is also effective. In particular, when not only a line pattern extending in a predetermined direction but also a plurality of line patterns extending in different directions (a mixture of line and space patterns having different periodic directions) is included in the mask (reticle) pattern, Similarly, as disclosed in Japanese Patent Laid-Open No. 6-53120, an aperture of the projection optical system can be obtained by using both the polarization illumination method that linearly polarizes in the tangential direction of the circle centered on the optical axis and the annular illumination method. Even when the number NA is large, high imaging performance can be obtained. For example, a polarized illumination method and an annular illumination method (annular ratio) in which a half-tone phase shift mask having a transmittance of 6% (a pattern having a half pitch of about 63 nm) is linearly polarized in a tangential direction of a circle around the optical axis. 3/4), when the illumination σ is 0.95 and the numerical aperture of the projection optical system PL is NA = 1.00, the depth of focus (DOF) is more than that of using randomly polarized light. If the projection optical system has a numerical aperture NA = 1.2 with a pattern with a half pitch of about 55 nm, the depth of focus can be increased by about 100 nm.

  In the present embodiment, the optical element 2 is attached to the tip of the projection optical system PL, and the optical characteristics of the projection optical system PL, for example, aberration (spherical aberration, coma aberration, etc.) can be adjusted by this lens. The optical element attached to the tip of the projection optical system PL may be an optical plate used for adjusting the optical characteristics of the projection optical system PL. Alternatively, it may be a plane parallel plate that can transmit the exposure light EL.

  When the pressure between the optical element at the tip of the projection optical system PL generated by the flow of the liquid LQ and the substrate P is large, the optical element is not exchangeable but the optical element is moved by the pressure. It may be fixed firmly so that there is no.

  In the present embodiment, the space between the projection optical system PL and the surface of the substrate P is filled with the liquid LQ. However, for example, the liquid with the cover glass made of a plane-parallel plate attached to the surface of the substrate P is used. The structure which satisfy | fills LQ may be sufficient.

The liquid LQ of the present embodiment is water, but may be a liquid other than water. For example, when the light source of the exposure light EL is an F ₂ laser, the F ₂ laser light does not pass through water. The liquid LQ may be, for example, a fluorinated fluid such as perfluorinated polyether (PFPE) or fluorinated oil that can transmit F ₂ laser light. In this case, the lyophilic treatment is performed by forming a thin film with a substance having a molecular structure having a small polarity including fluorine, for example, at a portion in contact with the liquid LQ. In addition, as the liquid LQ, the liquid LQ is transmissive to the exposure light EL, has a refractive index as high as possible, and is stable with respect to the photoresist applied to the projection optical system PL and the surface of the substrate P (for example, Cedar). Oil) can also be used. Also in this case, the surface treatment is performed according to the polarity of the liquid LQ to be used.

  The substrate P in each of the above embodiments is not only a semiconductor wafer for manufacturing a semiconductor device, but also a glass substrate for a display device, a ceramic wafer for a thin film magnetic head, or an original mask or reticle used in an exposure apparatus. (Synthetic quartz, silicon wafer) or the like is applied.

  As the exposure apparatus EX, in addition to the step-and-scan type scanning exposure apparatus (scanning stepper) that scans and exposes the pattern of the mask M by moving the mask M and the substrate P synchronously, the mask M and the substrate P Can be applied to a step-and-repeat type projection exposure apparatus (stepper) in which the pattern of the mask M is collectively exposed while the substrate P is stationary and the substrate P is sequentially moved stepwise.

  Further, as the exposure apparatus EX, a reduced image of the first pattern is projected with the first pattern and the substrate P being substantially stationary (for example, a refraction type projection optical system that does not include a reflecting element at 1/8 reduction magnification). The present invention can also be applied to an exposure apparatus that performs batch exposure on the substrate P using the above. In this case, after that, with the second pattern and the substrate P substantially stationary, a reduced image of the second pattern is collectively exposed onto the substrate P by partially overlapping the first pattern using the projection optical system. It can also be applied to a stitch type batch exposure apparatus. Further, the stitch type exposure apparatus can be applied to a step-and-stitch type exposure apparatus in which at least two patterns are partially transferred on the substrate P, and the substrate P is sequentially moved.

  The present invention can also be applied to a twin stage type exposure apparatus disclosed in Japanese Patent Application Laid-Open No. 10-163099, Japanese Patent Application Laid-Open No. 10-214783, and Japanese Translation of PCT International Publication No. 2000-505958.

  In the above-described embodiment, an exposure apparatus that locally fills the liquid between the projection optical system PL and the substrate P is employed. However, the present invention is disclosed in Japanese Patent Laid-Open No. 6-124873. It is also applicable to an immersion exposure apparatus that moves a stage holding a substrate to be exposed in a liquid tank.

  The type of the exposure apparatus EX is not limited to an exposure apparatus for manufacturing a semiconductor element that exposes a semiconductor element pattern on the substrate P, but an exposure apparatus for manufacturing a liquid crystal display element or a display, a thin film magnetic head, an image sensor (CCD). ) Or an exposure apparatus for manufacturing reticles or masks.

  As described above, the exposure apparatus EX according to the present embodiment maintains various mechanical subsystems including the respective constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Manufactured by assembling. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy. The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus. The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  As shown in FIG. 7, a microdevice such as a semiconductor device includes a step 201 for designing a function / performance of the microdevice, a step 202 for producing a mask (reticle) based on the design step, and a substrate as a base material of the device. Manufacturing step 203, exposure processing step 204 for exposing the mask pattern onto the substrate by the exposure apparatus EX of the above-described embodiment, device assembly step (including dicing process, bonding process, packaging process) 205, inspection step 206, etc. It is manufactured after.

It is a schematic block diagram which shows one Embodiment of exposure apparatus. FIG. 2 is an enlarged view of FIG. 1 for explaining a liquid immersion mechanism. It is a mimetic diagram showing one embodiment of a piping system. It is a mimetic diagram showing one embodiment of a piping system. It is a figure which shows another example of a liquid collection | recovery mechanism. It is a schematic block diagram which shows another embodiment of exposure apparatus. It is a flowchart figure which shows an example of the manufacturing process of a semiconductor device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid immersion mechanism, 10 ... Liquid supply mechanism, 12 ... Liquid supply port, 20 ... Liquid recovery mechanism, 22 ... Liquid recovery port, 23 ... Recovery pipe (piping system), 29 ... Filter member (removal device), 40 ... Second liquid recovery mechanism 51 ... Upper surface 60 ... Measuring device 70 ... Nozzle member 80 ... Third liquid recovery mechanism 90 ... Functional liquid supply device EX ... Exposure device INF ... Notification device LQ ... Liquid, P ... Substrate, PST ... Substrate stage, Pg ... Photosensitive material, S ... Corrosion-resistant material

Claims (30)

In an exposure apparatus that exposes a substrate through a liquid,
A liquid recovery mechanism for recovering the liquid;
A measuring device for measuring the acidity of the recovered liquid ,
The exposure apparatus according to claim 1, wherein at least a part of a liquid contact surface that contacts the recovered liquid in the liquid recovery mechanism has corrosion resistance to the liquid. 2. The exposure apparatus according to claim 1, wherein the predetermined member having the liquid contact surface is made of a material having corrosion resistance to the liquid. 3. An exposure apparatus according to claim 2, further comprising a piping system through which the collected liquid flows, wherein the piping system is formed of the material. 2. The exposure apparatus according to claim 1, wherein the liquid contact surface is coated with a material having corrosion resistance to the liquid . The exposure apparatus according to claim 2, wherein the material includes a fluorine-based resin. The exposure apparatus according to claim 2, wherein the material includes stainless steel. A nozzle member provided to face the substrate surface and having a recovery port for recovering a liquid;
  Of the nozzle member, a contact surface that contacts the liquid disposed on the substrate, and at least a part of the inner wall surface of the internal flow path formed in the nozzle member and connected to the recovery port are corrosion resistant. The exposure apparatus according to claim 1, wherein the exposure apparatus is provided. Having a substrate stage movable while holding the substrate;
  The substrate stage has an upper surface disposed around a substrate held by the substrate stage;
  The exposure apparatus according to claim 1, wherein the upper surface is corrosion resistant. The exposure apparatus according to claim 1, further comprising a supply device that supplies a functional liquid to the liquid contact surface of the liquid recovery mechanism based on a measurement result of the measurement device.   The exposure apparatus according to claim 1, wherein the liquid recovery mechanism includes a removal device for reducing or removing a predetermined substance contained in the recovered liquid. In an exposure apparatus that exposes a substrate through a liquid,
  A liquid recovery mechanism for recovering the liquid;
  A measuring device for measuring the acidity of the recovered liquid;
With
  The exposure apparatus according to claim 1, wherein the liquid recovery mechanism includes a removal device for reducing or removing a predetermined substance contained in the recovered liquid. The exposure apparatus according to claim 10 or 11, wherein the removing apparatus removes an acid contained in the collected liquid. The exposure apparatus according to claim 10, wherein the removing device includes a filter member provided at a predetermined position of a flow path through which the collected liquid flows. The exposure apparatus according to claim 1, wherein the liquid recovery mechanism recovers a liquid in contact with the substrate. The exposure apparatus according to claim 1, wherein the measurement apparatus includes a pH monitor. The exposure apparatus according to claim 1, further comprising a notification device that notifies a measurement result of the measurement device. The exposure apparatus according to claim 1, wherein the recovered liquid contains an acid. A device manufacturing method using the exposure apparatus according to any one of claims 1 to 17. A liquid recovery method in an exposure apparatus that exposes a substrate through a liquid,
  Recovering the liquid by the liquid recovery mechanism;
  Measuring the acidity of the recovered liquid,
  The liquid recovery mechanism is a liquid recovery method in which at least a part of a liquid contact surface that contacts the recovered liquid has corrosion resistance to the liquid. The liquid recovery method according to claim 19, further comprising supplying a functional liquid to the liquid contact surface based on the measurement result . 21. The liquid recovery method according to claim 19 or 20, further comprising reducing or removing a predetermined substance contained in the recovered liquid. A liquid recovery method in an exposure apparatus that exposes a substrate through a liquid,
  Collecting the liquid;
  Measuring the acidity of the recovered liquid;
  Reducing or removing predetermined substances contained in the recovered liquid;
A liquid recovery method comprising: 23. The liquid recovery method according to claim 21, wherein the reduction or removal of the predetermined substance is performed by a filter member provided at a predetermined position of a flow path through which the recovered liquid flows. The liquid recovery method according to any one of claims 21 to 23, wherein the reduction or removal of the predetermined substance includes removal of an acid contained in the recovered liquid. 25. The liquid recovery method according to any one of claims 21 to 24, wherein the measurement includes measurement of acidity of the liquid in which the predetermined substance is reduced or removed. The liquid recovery method according to any one of claims 19 to 25, wherein the recovered liquid includes a liquid in contact with the substrate. The liquid recovery method according to any one of claims 19 to 26, wherein the recovered liquid contains an acid. The liquid recovery method according to any one of claims 19 to 27, wherein the measurement of the recovered liquid is performed during exposure of the substrate. The liquid recovery method according to any one of claims 19 to 28, wherein the measurement of the recovered liquid is performed before exposure of the substrate. 30. The liquid recovery method according to any one of claims 19 to 29, wherein the measurement of the recovered liquid is performed after exposure of the substrate.

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