JP2010056453A - Exposure system, exposure method, and device manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure system that prevents the occurrence of exposure failures. <P>SOLUTION: The exposure system exposes a substrate, by irradiating exposure light thereto through an optical projection system. The exposure system includes a first detection device that detects a first reference mark, by allowing at least a portion thereof to be disposed above the body side of the optical projection system and by irradiating detection light via the optical projection system to a first reference mark disposed under the imaging surface side of the optical projection system. When the substrate is not exposed, the first detection device has the detection light irradiated onto a predetermined member disposed under the image surface side via the optical projection system, and optical cleaning of the predetermined member is carried out. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

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

An exposure apparatus that exposes a substrate by irradiating the substrate with exposure light via a projection optical system, as disclosed in the following patent document, in a manufacturing process of a microdevice such as a semiconductor device or an electronic device is known. Yes.
US Patent Publication No. 2006/0187432 US Patent Publication No. 2007/0258072

  If a member in the exposure apparatus is contaminated, for example, an exposure failure may occur, and as a result, a defective device may occur. Therefore, it is desired to devise a technique that can efficiently and satisfactorily clean the members in the exposure apparatus.

  An object of an aspect of the present invention is to provide an exposure apparatus and an exposure method that can suppress the occurrence of exposure failure. Another object of the present invention is to provide a device manufacturing method that can suppress the occurrence of defective devices.

  According to the first aspect of the present invention, there is provided an exposure apparatus that exposes a substrate by irradiating the substrate with exposure light via the projection optical system, wherein at least a part of the exposure apparatus is disposed on the object plane side of the projection optical system, A first detection device capable of detecting the first reference mark by irradiating the first reference mark disposed on the image plane side of the projection optical system via the projection optical system and detecting the first reference mark, An exposure apparatus is provided that irradiates a predetermined member disposed on the image plane side with a detection optical beam via a projection optical system and optically cleans the predetermined member when the substrate is not exposed.

  According to a second aspect of the present invention, there is provided a device manufacturing method including exposing a substrate using the exposure apparatus according to the first aspect and developing the exposed substrate.

  According to a third aspect of the present invention, there is provided an exposure method for exposing a substrate by irradiating the substrate with exposure light through the projection optical system, wherein at least a part of the exposure method is disposed on the object plane side of the projection optical system. Using the first detection device, the first reference mark arranged on the image plane side of the projection optical system is irradiated with detection light via the projection optical system to detect the first reference mark, and the detection result The position of the substrate is adjusted using the position information of the projection image obtained by the projection optical system acquired based on the exposure of the substrate, and when the substrate is not exposed, the first detection device is used to pass through the projection optical system. An exposure method is provided that includes irradiating a predetermined member arranged on the image plane side with detection light and optically washing the predetermined member.

  According to a fourth aspect of the present invention, there is provided a device manufacturing method including exposing a substrate using the exposure method of the third aspect and developing the exposed substrate.

  According to the present invention, the occurrence of defective exposure can be suppressed, and the occurrence of defective devices can be suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited thereto. In the following description, an XYZ orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to this XYZ orthogonal coordinate system. A predetermined direction in the horizontal plane is defined as an X-axis direction, a direction orthogonal to the X-axis direction in the horizontal plane is defined as a Y-axis direction, and a direction orthogonal to each of the X-axis direction and the Y-axis direction (that is, a vertical direction) is defined as a Z-axis direction. In addition, the rotation (inclination) directions around the X, Y, and Z axes are the θX, θY, and θZ directions, respectively.

  FIG. 1 is a schematic block diagram that shows an example of an exposure apparatus EX according to the present embodiment. The exposure apparatus EX of the present embodiment is an immersion exposure apparatus that exposes a substrate P with exposure light EL through a liquid LQ. In the present embodiment, water (pure water) is used as the liquid LQ.

  In FIG. 1, an exposure apparatus EX performs a mask stage 1 that can move while holding a mask M, a substrate stage 2 that can move while holding a substrate P, and a measurement process related to exposure without holding the substrate P. An image of the pattern of the mask M illuminated with the exposure light EL, the measurement stage 3 mounted with the measurement member (measuring instrument) C to be executed, and movable, the illumination system IL that illuminates the mask M with the exposure light EL A projection optical system PL for projecting the light onto the substrate P, a liquid immersion member 4 capable of forming the liquid immersion space LS so that at least a part of the optical path of the exposure light EL is filled with the liquid LQ, a mask stage 1, and a substrate stage 2 , And an interferometer system 5 that measures positional information of the measurement stage 3, and at least a part of the first reference mark FM1 that is disposed on the object plane side of the projection optical system PL and disposed on the image plane side of the projection optical system PL. Can be detected The first alignment system 6, the second alignment system 7 capable of detecting the second reference mark FM2 arranged on the image plane side of the projection optical system PL in a predetermined positional relationship with the first reference mark FM1, and the entire exposure apparatus EX A control device 8 that controls the operation, a storage device 8M that is connected to the control device 8 and stores various information relating to exposure, and a timer 9 that is connected to the control device 8 and can measure time are provided.

  The mask M includes a reticle on which a device pattern projected onto the substrate P by the projection optical system PL is formed. The mask M includes a transmission type mask in which a predetermined pattern is formed on a transparent plate such as a glass plate using a light shielding film such as chromium. A reflective mask can also be used as the mask M.

  The substrate P is a substrate for manufacturing a device. The substrate P includes, for example, a base material such as a semiconductor wafer and a photosensitive film formed on the base material. The photosensitive film is a film of a photosensitive material (photoresist). Further, the substrate P may include another film in addition to the photosensitive film. For example, the substrate P may include an antireflection film or a protective film (topcoat film) that protects the photosensitive film.

  The measuring member (measuring instrument) C executes a measurement process related to exposure. In the present embodiment, the measurement stage 3 has a plurality of measurement members C. In the present embodiment, the measurement stage 3 includes measurement members C1, C2, and C3. In the present embodiment, the exposure light EL emitted from the projection optical system PL is incident on the measurement members C1 and C2. The measurement member C3 is a reference member on which the first reference mark FM1 and the second reference mark FM2 are arranged. An example of an exposure apparatus that includes a substrate stage that can move while holding a substrate and a measurement stage that can move by mounting a measurement member (measuring instrument) without holding the substrate is, for example, the United States. It is disclosed in Japanese Patent No. 6897963, US Patent Application Publication No. 2007/0127006, and the like.

The illumination system IL irradiates the predetermined illumination area IR with the exposure light EL. The illumination area IR includes a position where the exposure light EL emitted from the illumination system IL can be irradiated. The illumination system IL illuminates at least a part of the mask M arranged in the illumination region IR with the exposure light EL having a uniform illuminance distribution. As the exposure light EL emitted from the illumination system IL, for example, far ultraviolet light (DUV light) such as bright lines (g-line, h-line, i-line) and KrF excimer laser light (wavelength 248 nm) emitted from a mercury lamp, ArF Excimer laser light (wavelength 193 nm), vacuum ultraviolet light (VUV light) such as F ₂ laser light (wavelength 157 nm), or the like is used. In the present embodiment, ArF excimer laser light that is ultraviolet light (vacuum ultraviolet light) is used as the exposure light EL.

  The mask stage 1 is movable while holding the mask M on the object plane side of the projection optical system PL. The mask stage 1 is movable on the guide surface 11G of the first surface plate 11 with respect to the illumination area IR.

  In the present embodiment, the mask stage 1 can move in six directions on the guide surface 11G in the X axis, Y axis, Z axis, θX, θY, and θZ directions by the operation of the drive system 13. In the present embodiment, the drive system 13 includes a planar motor as disclosed in, for example, US Pat. No. 6,452,292. In the present embodiment, the planar motor for moving the mask stage 1 includes a mover 1M disposed on the mask stage 1 and a stator 11C disposed on the first surface plate 11. In the present embodiment, the mover 1M includes a magnet array, and the stator 11C includes a coil array. The mover 1M may include a coil array, and the stator 11C may include a magnet array.

  The projection optical system PL irradiates the predetermined projection region PR with the exposure light EL. The projection region PR includes a position where the exposure light EL emitted from the projection optical system PL can be irradiated. The projection optical system PL projects an image of the pattern of the mask M at a predetermined projection magnification onto at least a part of the substrate P arranged in the projection region PR. The projection optical system PL of the present embodiment is a reduction system whose projection magnification is, 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. In the present embodiment, the optical axis AX of the projection optical system PL is parallel to the Z axis. The projection optical system PL may be any of a refractive system that does not include a reflective optical element, a reflective system that does not include a refractive optical element, and a catadioptric system that includes a reflective optical element and a refractive optical element. Further, the projection optical system PL may form either an inverted image or an erect image.

  The substrate stage 2 is movable while holding the substrate P on the image plane side of the projection optical system PL. The substrate stage 2 is movable with respect to the projection region PR on the guide surface 12G of the second surface plate 12.

  The measurement stage 3 is movable with the measurement member C mounted on the image plane side of the projection optical system PL. The measurement stage 3 is movable with respect to the projection region PR on the guide surface 12G of the second surface plate 12.

  In the present embodiment, each of the substrate stage 2 and the measurement stage 3 is moved in six directions on the guide surface 12G in the X axis, Y axis, Z axis, θX, θY, and θZ directions by the operation of the drive system 14. It is movable. In this embodiment, the drive system 14 includes a planar motor as disclosed in, for example, US Pat. No. 6,452,292. In the present embodiment, the planar motor for moving the substrate stage 2 includes a mover 2M disposed on the substrate stage 2 and a stator 12C disposed on the second surface plate 12. The planar motor for moving the measurement stage 3 includes a mover 3M disposed on the measurement stage 3 and a stator 12C disposed on the second surface plate 12. In the present embodiment, the movers 2M and 3M include a magnet array, and the stator 12C includes a coil array. The movers 2M and 3M may include a coil array, and the stator 12C may include a magnet array.

  The interferometer system 5 includes a laser interferometer unit 5A that measures position information of the mask stage 1 and a laser interferometer unit 5B that measures position information of the substrate stage 2 and the measurement stage 3. The laser interferometer unit 5 </ b> A can measure position information of the mask stage 1 using a measurement mirror 1 </ b> R disposed on the mask stage 1. The laser interferometer unit 5 </ b> B can measure the position information of the substrate stage 2 and the measurement stage 3 using the measurement mirror 2 </ b> R disposed on the substrate stage 2 and the measurement mirror 3 </ b> R provided on the measurement stage 3. When executing the exposure process of the substrate P or when executing the predetermined measurement process, the control device 8 operates the drive systems 13 and 14 based on the measurement result of the interferometer system 5 to thereby perform the mask stage 1 (mask M), position control of the substrate stage 2 (substrate P) and the measurement stage 3 (measuring instrument C) is executed.

  The first alignment system 6 includes an emission unit 6A that emits detection light LA for irradiating a mark to be detected, and a detection unit 6B that detects a mark irradiated with the detection light LA. The detection unit 6B includes a light receiving unit that can receive at least part of light from the irradiated portion irradiated with the detection light LA. At least a part of the first alignment system 6 is disposed on the object plane side of the projection optical system PL. In the present embodiment, in the first alignment system 6, at least the emission unit 6A and the detection unit 6B are arranged on the object plane side of the projection optical system PL.

  The first alignment system 6 of the present embodiment irradiates the detection light LA to the mark to be detected as disclosed in, for example, US Pat. No. 5,646,413, and the mark obtained by a CCD camera or the like. This is a VRA (Visual Reticle Alignment) type alignment system that performs image processing of the image data and detects the position of the mark. In the present embodiment, the detection light LA is ultraviolet light. In the present embodiment, the detection light LA has substantially the same wavelength as the exposure light EL and can pass through the projection optical system PL.

  The first alignment system 6 detects the first reference mark FM1 by irradiating the first reference mark FM1 arranged on the image plane side of the projection optical system PL with the detection light LA via the projection optical system PL. In the present embodiment, the first fiducial mark FM1 is disposed on the measurement member C3 mounted on the measurement stage 3. When detecting the first fiducial mark FM1, the first alignment system 6 emits the detection light LA from the emission unit 6A arranged on the object plane side of the projection optical system PL. The detection light LA emitted from the emission unit 6A is applied to an area including the first reference mark FM1 disposed on the image plane side of the projection optical system PL via the projection optical system PL. The detection unit 6B receives light from the region irradiated with the detection light LA through the projection optical system PL, and acquires image data of the first reference mark FM1.

  The first alignment system 6 detects the first reference mark FM1 through the third reference mark FM3 and the projection optical system PL arranged on the object plane side of the projection optical system PL, and uses the projection optical system PL. Position information of the projected image can be acquired. That is, the first alignment system 6 irradiates the first reference mark FM1 with the detection light LA, and converts the image of the first reference mark FM1 and the image of the third reference mark FM3 formed by the reflected light into the CCD. The position information of the projection image by the projection optical system PL can be acquired by imaging using an imaging element such as the above and performing image processing on these imaging signals. In the present embodiment, the third fiducial mark FM3 is disposed on the optical member 15 disposed on the mask stage 1.

  The first alignment system 6 can detect the first alignment mark AM1 arranged on the mask M. The first alignment system 6 can detect the position of the projection image by the projection optical system PL by detecting the first reference mark FM1 via the first alignment mark AM1 disposed on the mask M and the projection optical system PL. It is. That is, the first alignment system 6 irradiates the first reference mark FM1 with the detection light LA, and converts the image of the first reference mark FM1 and the image of the first alignment mark AM1 formed by the reflected light into the CCD. The position information of the projection image by the projection optical system PL can be acquired by imaging using an imaging element such as the above and performing image processing on these imaging signals.

  The second alignment system 7 includes an emission unit 7A that emits the detection light LB for irradiating the detection target mark, and a detection unit 7B that detects the mark irradiated with the detection light LB. In the present embodiment, the second alignment system 7 is a so-called off-axis alignment system, and detects a mark to be detected without using the projection optical system PL.

  The second alignment system 7 of this embodiment irradiates a detection target mark LB to a mark to be detected as disclosed in, for example, US Pat. No. 5,493,403, and receives light by reflected light from the mark. An FIA (Field Image Alignment) method that detects an image of a target mark and an index image formed on a surface using an image sensor such as a CCD and detects the position of the mark by performing image processing on the image signals. This is an alignment system. In the present embodiment, the detection light LB is broadband light that does not expose the photosensitive film of the substrate P.

  The second alignment system 7 can irradiate the second reference mark FM2 with the detection light LB, and can acquire an image of the second reference mark FM2 without using the projection optical system PL. The second reference mark FM2 is disposed on the measurement member C3. The first fiducial mark FM1 and the second fiducial mark FM2 are arranged on the measurement member C3 with a predetermined positional relationship.

  The second alignment system 7 can detect the second alignment mark AM2 arranged on the substrate P. The second alignment system 7 can acquire the image of the second alignment mark AM2 without passing through the projection optical system PL by irradiating the second alignment mark AM2 with the detection light LB.

  The liquid immersion member 4 can form the liquid immersion space LS so that at least a part of the optical path of the exposure light EL is filled with the liquid LQ. The immersion space LS is a portion (space, region) filled with the liquid LQ. The liquid immersion member 4 is disposed in the vicinity of the terminal optical element 21 closest to the image plane of the projection optical system PL among the plurality of optical elements of the projection optical system PL. In the present embodiment, the liquid immersion member 4 is an annular member and is disposed around the optical path of the exposure light EL. In the present embodiment, at least a part of the liquid immersion member 4 is disposed around the terminal optical element 21.

  The last optical element 21 has an exit surface 22 that emits the exposure light EL toward the image plane of the projection optical system PL. In the present embodiment, the immersion space LS is an exposure light EL between the terminal optical element 21 and an object arranged at a position (projection region PR) where the exposure light EL emitted from the terminal optical element 21 can be irradiated. Are formed so as to be filled with the liquid LQ. In the present embodiment, the object that can be arranged in the projection region PR includes at least one of the substrate stage 2, the substrate P held on the substrate stage 2, the measurement stage 3, and the measurement member C mounted on the measurement stage 3. .

  In the present embodiment, the liquid immersion member 4 has a lower surface 23 that can face an object arranged in the projection region PR. By holding the liquid LQ between the exit surface 22 and the lower surface 23 and the surface of the object, the immersion space so that the optical path of the exposure light EL between the last optical element 21 and the object is filled with the liquid LQ. LS is formed.

  In this embodiment, when the exposure light EL is irradiated to the substrate P, the immersion space LS is formed so that a partial region on the surface of the substrate P including the projection region PR is covered with the liquid LQ. At least a part of the interface (meniscus, edge) of the liquid LQ is formed between the lower surface 23 of the liquid immersion member 4 and the surface of the substrate P. That is, the exposure apparatus EX of the present embodiment employs a local liquid immersion method.

  The substrate stage 2 has an upper surface 24 that can face the emission surface 22 and the lower surface 23. The measurement stage 3 has an upper surface 25 that can face the emission surface 22 and the lower surface 23. In the present embodiment, the upper surfaces 24 and 25 are flat surfaces substantially parallel to the XY plane.

  In the present embodiment, as disclosed in, for example, U.S. Patent Application Publication No. 2007/0127006, the control device 8 approaches or contacts the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3. In this state, at least one of the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 is opposed to the exit surface 22 of the final optical element 21 and the lower surface 23 of the liquid immersion member 4, and the final optical element 21 and the liquid The substrate stage 2 and the measurement stage 3 can be synchronously moved in the XY directions with respect to the immersion member 4. As a result, the control device 8 is configured such that the immersion space LS is formed between the terminal optical element 21 and the liquid immersion member 4 and the substrate stage 2, and the terminal optical element 21, the liquid immersion member 4 and the measurement stage 3. It is possible to change from one of the states in which the immersion space LS is formed to the other.

  In the following description, at least one of the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 and the terminal optical element 21 in a state where the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 are approached or brought into contact with each other. The operation of causing the substrate stage 2 and the measurement stage 3 to move synchronously in the XY directions with respect to the last optical element 21 and the liquid immersion member 4 while making the emission surface 22 and the lower surface 23 of the liquid immersion member 4 face each other is appropriately scrammed. This is called movement.

  In this embodiment, when the scrum movement is executed, the control device 8 causes the upper surface 24 of the substrate stage 2 so that the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 are arranged in substantially the same plane. And the positional relationship between the measurement stage 3 and the upper surface 25 of the measurement stage 3 are adjusted.

  FIG. 2 is a side sectional view parallel to the YZ plane showing the vicinity of the liquid immersion member 4. In the description of FIG. 2, in order to simplify the description, a description will be mainly given of an example in which the terminal optical element 21 and the liquid immersion member 4 are opposed to the substrate P. As described above, objects other than the substrate P, such as the substrate stage 2 and the measurement stage 3, can be arranged at positions facing the terminal optical element 21 and the liquid immersion member 4.

  In the present embodiment, the liquid immersion member 4 has a plate portion 29 that is at least partially disposed between the exit surface 22 of the last optical element 21 and the surface of the substrate P in the Z-axis direction. The plate portion 29 has an opening 30 in the center. The exposure light EL emitted from the emission surface 22 can pass through the opening 30. For example, during exposure of the substrate P, the exposure light EL emitted from the emission surface 22 passes through the opening 30 and is irradiated onto the surface of the substrate P via the liquid LQ.

  The liquid immersion member 4 includes a supply port 33 that can supply the liquid LQ onto the substrate P and a recovery port 34 that can recover the liquid LQ on the substrate P. The supply port 33 is connected to the liquid supply device 36 via a flow path 37. The liquid supply device 36 can supply the supply port 33 with a clean and temperature-adjusted liquid LQ. The flow path 37 includes a supply flow path formed inside the liquid immersion member 4 and a flow path formed by a supply pipe that connects the supply flow path and the liquid supply device 36. The liquid LQ delivered from the liquid supply device 36 is supplied to the supply port 33 via the flow path 37. The supply port 33 is disposed at a predetermined position of the liquid immersion member 4 facing the optical path in the vicinity of the optical path. In the present embodiment, the supply port 33 supplies the liquid LQ to the space 31 between the emission surface 22 and the upper surface of the plate portion 29. The liquid LQ supplied from the supply port 33 to the space 31 is supplied onto the substrate P through the opening 30.

  The recovery port 34 can recover the liquid LQ on the substrate P facing the liquid immersion member 4. The recovery port 34 is connected to a liquid recovery device 38 via a flow path 39. The liquid recovery device 38 includes a vacuum system and can recover the liquid LQ by sucking it from the recovery port 34. The flow path 39 includes a recovery flow path formed inside the liquid immersion member 4 and a flow path formed by a recovery pipe that connects the recovery flow path and the liquid recovery device 38. The liquid LQ recovered from the recovery port 34 is recovered by the liquid recovery device 38 via the flow path 39.

  In the present embodiment, the recovery port 34 is disposed around the optical path of the exposure light EL. The recovery port 34 is disposed at a predetermined position of the liquid immersion member 4 that can face the surface of the substrate P. The recovery port 34 can recover at least a part of the liquid LQ on the substrate P facing the lower surface 23 of the liquid immersion member 4. In the present embodiment, a porous member 35 is disposed in the recovery port 34. The porous member 35 is a plate-like member including a plurality of openings (openings or pores). In the present embodiment, the porous member 35 includes a mesh plate in which a large number of small holes are formed in a mesh shape. The recovery port 34 recovers the liquid LQ through the hole of the porous member 35. As the porous member 35, a sintered member (for example, a sintered metal) in which a large number of pores are formed, a foamed member (for example, a foamed metal), or the like may be used.

  In the present embodiment, the lower surface 23 of the liquid immersion member 4 is disposed around the opening 30, the lower surface of the plate portion 29 that can face the substrate P, and the porous surface that is disposed around the lower surface and can face the substrate P. A lower surface of the member 35. The recovery port 34 can recover the liquid LQ on the substrate P that is in contact with the lower surface of the porous member 35.

  In the present embodiment, the control device 8 is in parallel with the liquid supply operation using the supply port 33 in order to form the immersion space LS with the liquid LQ between the terminal optical element 21 and the liquid immersion member 4 and the substrate P. Then, the liquid recovery operation using the recovery port 34 is executed. The liquid recovery operation using the recovery port 34 is executed, and the liquid recovery operation using the supply port 33 is executed, so that the last optical element 21 and the liquid immersion member 4 on one side and the substrate P (object) on the other side are performed. The immersion space LS is formed between the two.

  FIG. 3 is a plan view of the substrate stage 2 and the measurement stage 3 that hold the substrate P. In the present embodiment, as shown in FIG. 3, on the substrate P, a plurality of shot areas S that are exposure target areas are set in a matrix. A second alignment mark AM2 is disposed on the substrate P. In the present embodiment, the second alignment mark AM2 is disposed adjacent to each of the shot regions S. The second alignment mark AM2 is detected by the second alignment system 7.

  The exposure apparatus EX of the present embodiment is a scanning exposure apparatus (so-called scanning stepper) that projects an image of the pattern of the mask M onto the substrate P while synchronously moving the mask M and the substrate P in a predetermined scanning direction. During exposure of the shot region S of the substrate P, the mask M and the substrate P are moved in a predetermined scanning direction in the XY plane. In the present embodiment, the scanning direction (synchronous movement direction) of the substrate P is the Y-axis direction, and the scanning direction (synchronous movement direction) of the mask M is also the Y-axis direction. The control device 8 moves the shot area S of the substrate P in the Y-axis direction with respect to the projection area PR, and in synchronization with the movement of the substrate P in the Y-axis direction, While moving the pattern area MA in the Y-axis direction, the exposure light EL is irradiated onto the substrate P through the projection optical system PL and the liquid LQ in the immersion space LS. Thereby, the shot area S of the substrate P is exposed through the liquid LQ with the exposure light EL from the projection optical system PL (terminal optical element 21), and the pattern image of the mask M is projected onto the shot area S of the substrate P. Is done.

  As described above, the measurement stage 3 includes the measurement members C1, C2, and C3. When the measurement process using the measurement members C1 and C2 is executed, the exposure light EL emitted from the terminal optical element 21 of the projection optical system PL is irradiated to the measurement members C1 and C2. The measurement members C1 and C2 have a transmission part that can transmit the exposure light EL. The exposure light EL that has passed through the transmission part enters the optical sensor. The optical sensor is arranged, for example, inside the measurement stage 3. Note that an optical sensor may be disposed outside the stage 3, and the exposure light EL that has passed through the measuring members C1 and C2 may be supplied to the optical sensor via a relay optical system.

  In this embodiment, the measurement member C1 constitutes at least a part of an aerial image measurement system capable of measuring an aerial image by the projection optical system PL as disclosed in, for example, US Patent Application Publication No. 2002/0041377. To do. The measuring member C2 constitutes at least a part of a wavefront aberration measuring system as disclosed in, for example, European Patent No. 1079223. Note that the measurement member C1 (or C2) is at least a part of an illuminance unevenness measurement system capable of measuring the illuminance unevenness of the exposure light EL as disclosed in, for example, US Pat. In at least a part of a measurement system capable of measuring the amount of variation in the transmittance of the exposure light EL of the projection optical system PL as disclosed in the specification of the US Patent Application Publication No. 2002/0061469, etc. You may comprise at least one part of the irradiation amount measurement system (illuminance measurement system) as disclosed.

  FIG. 4 is a side sectional view schematically showing an example of the measuring member C1 according to the present embodiment. In the present embodiment, the surface of the measuring member C <b> 1 is formed of the liquid repellent film 52. In the present embodiment, the measurement member C1 includes a base material 50 made of, for example, quartz glass, a light shielding film 51 disposed on the base material 50, an intermediate film 54 covering the light shielding film 51 and the transmission portion 53, and an intermediate A liquid repellent film 52 covering the film 54. The light shielding film 51 includes, for example, chromium, and is patterned so that the transmission part 53 is formed in a part thereof.

The intermediate film 54 is made of a light transmissive material. In the present embodiment, the intermediate film 54 is made of, for example, SiO ₂ (liquefied hardening SiO ₂ ).

  The liquid repellent film 52 is liquid repellent with respect to the liquid LQ. As described above, in the present embodiment, the liquid LQ is water, and the liquid repellent film 52 is water repellent. In the present embodiment, the liquid repellent film 52 is a resin film containing fluorine. Examples of the material for forming the liquid repellent film 52 include PFA (Tetrafluoroethylene-perfluoroalkylvinylether copolymer), PTFE (Polytetrafluoroethylene), PEEK (polyetheretherketone), and Teflon (registered trademark).

  A part of the liquid repellent film 52 may be omitted. For example, the liquid repellent film 52 does not have to be provided in a portion irradiated with the exposure light EL for measurement.

  The measurement member C3 is a reference member on which the first and second reference marks FM1 and FM2 are arranged. As described above, the first fiducial mark FM1 is detected by the first alignment system 6 via the projection optical system PL. As described above, the second fiducial mark FM2 is detected by the second alignment system 7 without passing through the projection optical system PL. When the first fiducial mark FM1 is detected by the first alignment system 6, the detection light LA emitted from the first alignment system 6 is at least part of the surface of the measuring member C3 including the first fiducial mark FM1. Irradiated. Further, when the second reference mark FM2 is detected by the second alignment system 7, the detection light emitted from the second alignment system 7 in at least a partial region of the surface of the measurement member C3 including the second reference mark FM2. LB is irradiated.

  Similar to the measurement member C1, the surface of the measurement member C2 is formed of a liquid repellent film. Also in this case, a part of the surface of the measurement member C2 (a portion irradiated with the exposure light EL) may not have a liquid repellent film. Further, like the measurement member C1, the surface of the measurement member C3 is formed of a liquid repellent film. Also in this case, a part of the surface of the measurement member C3 (a portion irradiated with the detection light LA, that is, a region including the first reference mark FM1) may not have a liquid repellent film.

  FIG. 5 is a side sectional view showing the vicinity of the mask stage 1, and FIG. 6 is a plan view showing the positional relationship between the mask stage 1 and the first alignment system 6.

  As shown in FIGS. 5 and 6, in the present embodiment, the mask stage 1 has an optical member 15 on which the third fiducial mark FM3 is arranged. The optical member 15 is disposed on the object plane side of the projection optical system PL. The optical member 15 includes a base material made of, for example, quartz glass, and a light shielding film disposed on the base material. The third fiducial mark FM3 is formed by patterning the light shielding film.

  In the present embodiment, the first alignment system 6 includes first and second detection units 61 and 62 each including an emission unit 6A and a detection unit 6B. In the present embodiment, the first detection unit 61 is disposed on the + X side with respect to the center (center in the XY plane) of the mask stage 1 at least a part of which is disposed in the illumination region IR, for example. 62 is arranged on the −X side. Each of the first and second detection units 61 and 62 is movable in the X-axis direction with respect to the optical path (mask stage 1) of the exposure light EL.

  In the present embodiment, the third reference mark FM3 is disposed on the optical member 15 so as to correspond to the first and second detection units 61 and 62, respectively.

  Further, in the present embodiment, the optical member 15 includes a transmission portion 16 that can transmit the detection light LA emitted from the first alignment system 6. The third fiducial mark FM3 is arranged at a predetermined position of the optical member 15 different from the transmission part 16. In the present embodiment, the transmissive portion 16 is disposed at a position adjacent to the third reference mark FM3. The transmission part 16 and the third reference mark FM3 are separated from each other in the Y-axis direction. In the present embodiment, the transmission part 16 is a partial region of the base material of the optical member 15 where the light shielding film and the reference mark are not arranged.

  In the present embodiment, the mask stage 1 includes a first holding part 17 that holds the mask M so as to be releasable, and a second holding part 18 that holds the optical member 15 so as to be releasable. The first holding unit 17 is disposed at least at a part around the first opening 71 formed in a part of the mask stage 1. The second holding unit 18 is disposed at least at a part around the second opening 72 formed in a part of the mask stage 1. In the present embodiment, the first opening 71 and the second opening 72 are arranged apart from each other in the Y-axis direction. The optical member 15 may not be releasable.

  The mask M of the present embodiment has a pattern area MA in which a pattern is formed. The first holding unit 17 holds at least a part of the mask M other than the pattern area MA. The second holding unit 18 holds at least a partial region of the optical member 15 other than the region where the third reference mark FM3 and the transmission unit 16 are disposed. The first holding unit 17 holds the mask M so that the pattern area MA of the mask M is disposed in the first opening 71. The second holding unit 18 holds the optical member 15 so that the third reference mark FM3 and the transmission unit 16 are disposed in the second opening 72.

  The first surface plate 11 has an opening 73 on the optical path of the exposure light EL. When performing the exposure processing of the substrate P, the position of the mask stage 1 is controlled so that the first opening 71 is disposed on the optical path of the exposure light EL. The exposure light EL emitted from the illumination system IL and irradiating the mask M enters the projection optical system PL via the first opening 71 and the opening 73. The exposure light EL that has entered the projection optical system PL is irradiated onto the image plane side of the projection optical system PL via the projection optical system PL.

  The opening 73 of the first surface plate 11 is disposed on the optical path of the detection light LA. When the process using the first alignment system 6 and the optical member 15 is executed, the position of the mask stage 1 is controlled so that the second opening 72 is arranged on the optical path of the detection light LA. The detection light LA emitted from the first alignment system 6 and passing through the optical member 15 enters the projection optical system PL via the second opening 72 and the opening 73. The detection light LA incident on the projection optical system PL is emitted from the exit surface of the projection optical system PL via the projection optical system PL.

  Next, an example of operations related to the alignment process using the exposure apparatus EX having the above-described configuration and the exposure process of the substrate P will be described.

  In order to load (load) the substrate P before exposure onto the substrate stage 2, the control device 8 places the substrate stage 2 at a predetermined substrate exchange position different from the position where the exposure light EL can be irradiated (projection region PR). Moving. When the substrate stage 2 is away from the projection region PR, the measurement stage 3 is disposed in the projection region PR, and the liquid LQ is held between the terminal optical element 21 and the liquid immersion member 4 and the measurement stage 3, and the liquid immersion space. LS is formed. The control device 8 executes measurement processing using the measurement stage 3 as necessary.

  The measurement process using the measurement stage 3 includes measurement (baseline measurement) of the relationship between the detection reference position of the second alignment system 7 and the position of the projection image of the projection optical system PL. The baseline measurement includes an operation of detecting the first fiducial mark FM1 by the first alignment system 6. In the present embodiment, when the first alignment system 6 detects the first fiducial mark FM1, as shown in FIG. 7, the position facing the terminal optical element 21 (detection light LA emitted from the emission surface 22 can be irradiated). 1st fiducial mark FM1 is arranged at the position. The control device 8 forms the immersion space LS with the liquid LQ so that the optical path between the projection optical system PL and the first reference mark FM1 of the measurement member C3 is filled with the liquid LQ.

  The first alignment system 6 includes a measurement member C3 disposed on the measurement stage 3 via the first alignment mark AM1 of the mask M disposed on the mask stage 1, the projection optical system PL, and the liquid LQ in the immersion space LS. The first reference mark FM1 is irradiated with the detection light LA and the reflected light is received to detect the positional relationship between the first reference mark FM1 and the first alignment mark AM1. The control device 8 acquires position information of the projected image by the projection optical system PL based on the detection result using the first alignment system 6.

  Further, the control device 8 detects the second fiducial mark FM2 of the measurement member C3 using the second alignment system 7. In the present embodiment, when the second alignment system 7 detects the second fiducial mark FM2, the second fiducial mark FM2 is arranged in the detection area of the second alignment system 7. The second alignment system 7 detects the second reference mark FM2 by irradiating the second reference mark FM2 with the detection light LB without using the liquid LQ. Thereby, the positional relationship between the detection reference position of the second alignment system 7 and the second reference mark FM2 is detected.

  In the present embodiment, the positional relationship between the first reference mark FM1 and the second reference mark FM2 is known. Further, the positional relationship between the first alignment mark AM1 and the pattern area MA of the mask M is known. The control device 8 includes a positional relationship between the first reference mark FM1 and the first alignment mark AM1, a positional relationship between the detection reference position of the second alignment system 7 and the second reference mark FM2, and the first reference mark FM1 and the first reference mark FM1. Based on the positional relationship with the second reference mark FM2, baseline information that is the relationship between the position of the projected image (pattern image) by the projection optical system PL and the detection reference position of the second alignment system 7 is obtained.

  In addition, the measurement process using the measurement stage 3 is not limited to the baseline measurement, and may include a measurement process using the measurement member C (C1 and / or C2). In the present embodiment, when the measurement process using the measurement member C is executed, the projection optical system PL (terminal optical element 21) so that the optical path between the projection optical system PL and the measurement member C is filled with the liquid LQ. The liquid LQ is held between the measuring member C and the liquid immersion space LS. The control device 8 irradiates the measuring member C with the exposure light EL via the projection optical system PL and the liquid LQ in the immersion space LS. The exposure light EL that is irradiated onto the image plane side of the projection optical system PL and passes through the measuring member C enters the optical sensor (light receiving element). Thereby, for example, at least one of the spatial image of the projection optical system PL, the wavefront aberration, the illuminance unevenness of the exposure light EL, and the transmittance of the exposure light EL of the projection optical system PL is measured. The control device 8 executes a predetermined process (for example, a calibration process of the projection optical system PL) based on the measurement result, and reflects the measurement result in the subsequent exposure of the substrate P.

  In the present embodiment, the three measurement members C1, C2, and C3 are mounted on the measurement stage 3, but the number of measurement members C is not limited to three, and may be one. There may be four or more.

  After the loading of the substrate P onto the substrate stage 2 is completed and the measurement process using the measurement stage 3 is completed, the control device 8 moves the substrate stage 2 (substrate P) relative to the detection region of the second alignment system 7. Then, the second alignment mark AM2 of the substrate P is detected using the second alignment system 7. The control device 8 determines the position information of the shot region S of the substrate P based on the detection result of the second alignment system 7.

  After the positional information of the shot area S of the substrate P is acquired, the control device 8 performs scram movement to form an immersion space LS between the last optical element 21 and the immersion member 4 and the measurement stage 3. The state is changed to a state in which the immersion space LS is formed between the terminal optical element 21 and the liquid immersion member 4 and the substrate stage 2. The control device 8 starts the exposure process for the substrate P. The control device 8 adjusts the position of the substrate P based on the position information of the shot region S of the substrate P obtained from the detection result of the second alignment mark AM2 of the substrate P and the baseline information, and the substrate P Are sequentially exposed via the projection optical system PL and the liquid LQ.

  After the exposure processing of the substrate P is completed, in order to carry out (unload) the exposed substrate P from the substrate stage 2, the control device 8 executes scram movement to perform the final optical element 21 and the liquid immersion member. An immersion space LS is formed between 4 and the measurement stage 3, and the substrate stage 2 is moved to the substrate exchange position. The substrate P after exposure is unloaded from the substrate stage 2 moved to the substrate exchange position, and the substrate P before exposure is loaded onto the substrate stage 2. Thereafter, the same processing as described above is repeated.

  By the way, for example, the surfaces of the measurement members C1, C2, and C3 arranged on the measurement stage 3 may be contaminated, or the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 may be contaminated.

  For example, during exposure of the substrate P, a substance (for example, an organic substance such as a photosensitive material) generated (peeled) from the substrate P may be mixed into the liquid LQ in the immersion space LS as a foreign substance (contaminant). Further, not only substances generated from the substrate P but also foreign substances floating in the air may be mixed into the liquid LQ in the immersion space LS. When the liquid LQ contacts the surface of the measuring member C (C1, C2, C3), the surface of the measuring member C may be contaminated. Similarly, the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 may be contaminated.

  If the state where the surface of the measurement member C is contaminated is left, for example, the measurement accuracy using the measurement member C may be reduced, or the liquid LQ supplied from the supply port 33 may be contaminated. . Also, leaving the state in which the upper surface 24 of the substrate stage 2 and the upper surface 25 of the measurement stage 3 are contaminated may cause the liquid LQ supplied from the supply port 33 to be contaminated. If these problems occur, exposure failure may occur.

  Therefore, in the present embodiment, the control device 8 cleans a member disposed on the image plane side of the projection optical system PL at a predetermined timing when the substrate P is not exposed.

  Next, an example of a method for cleaning a member arranged on the image plane side of the projection optical system PL will be described. Hereinafter, a case where the measurement member C3 is cleaned will be described as an example.

  In the present embodiment, the control device 8 uses the first alignment system 6 to clean the measuring member C3 disposed on the image plane side of the projection optical system PL. In the present embodiment, the first alignment system 6 irradiates the measurement member C3 disposed on the image plane side of the projection optical system PL with the detection light LA via the projection optical system PL when the substrate P is not exposed. Then, the measuring member C3 is optically cleaned.

  As described above, in the present embodiment, the detection light LA includes ultraviolet light. That is, in the present embodiment, the detection light LA is light having a light cleaning effect.

  FIG. 8 is a diagram illustrating an example of a state in which the measuring member C3 is optically cleaned. In the present embodiment, when the measuring member C3 is optically cleaned, the first alignment system 6 irradiates the measuring member C3 with the detection light LA without passing through the third reference mark FM3. Thereby, at least a part of the surface of the measuring member C3 is favorably irradiated with the detection light LA.

  In the present embodiment, when the measuring member C3 is optically cleaned, the first alignment system 6 irradiates the measuring member C3 with the detection light LA via the transmission part 16 of the optical member 15 and the projection optical system PL. By irradiating the detection light LA through the transmission part 16 of the optical member 15, the detection light LA is favorably irradiated to the image plane side of the projection optical system PL. In the present embodiment, at the time of optical cleaning of the measurement member C3, the detection light LA is irradiated to both the first reference mark FM1 and the second reference mark FM2 of the measurement member C3, but either one may be irradiated. . Further, at the time of optical cleaning of the measurement member C3, after the detection light LA is irradiated on one of the first reference mark FM1 and the second reference mark FM2, the measurement stage 3 may be moved and the other may be irradiated with the detection light. .

  Further, in the present embodiment, as shown in FIG. 8, during the optical cleaning of the measurement member C3, between the last optical element 21 and the liquid immersion member 4 of the projection optical system PL and the measurement member C3 (measurement stage 3). The liquid LQ is held and the immersion space LS is formed. That is, in the present embodiment, the control device 8 irradiates the surface of the measurement member C3 with the detection light LA in a state where the liquid LQ is in contact with the surface of the measurement member C3. Thereby, the surface of the measurement member C3 is optically cleaned well.

  In the present embodiment, the control device 8 executes the liquid LQ recovery operation using the recovery port 34 in parallel with the liquid LQ supply operation using the supply port 33 to form the immersion space LS. In this state, the surface of the measuring member C3 that is in contact with the liquid LQ in the immersion space LS is irradiated with the detection light LA. Thereby, the detection light LA can be irradiated on the surface of the measurement member C3 in a state where the surface of the measurement member C3 and the clean liquid LQ supplied from the supply port 33 are in contact with each other. Further, since the liquid LQ in the immersion space LS is recovered from the recovery port 34, optical cleaning can be performed while maintaining the cleanliness (cleanness) of the liquid LQ in the immersion space LS.

  The case where the first alignment system 6 optically cleans the measurement member C3 has been described above as an example. Similarly, the first alignment system 6 can irradiate the measurement members C1 and C2 with the detection light LA via the projection optical system PL, and optically wash the measurement members C1 and C2. When the measurement member C1 is optically cleaned, the measurement stage 3 is positioned so that at least the surface of the light transmission part 53 among the surface of the measurement member C1 is irradiated with the detection light LA. Similarly, when the measurement member C2 is optically cleaned, the measurement stage 3 is positioned so that the detection light LA is irradiated on the surface of the light transmission portion of the measurement member C2 among the surfaces of the measurement member C2. Further, the first alignment system 6 can irradiate the upper surface 25 of the measurement stage 3 and the upper surface 24 of the substrate stage 2 with the detection light LA via the projection optical system PL, and optically clean the upper surface. That is, the object of light cleaning is not limited to the measurement member C. If it can be arranged on the image plane side of the projection optical system PL, it can be an object of light cleaning.

  In the present embodiment, the optical cleaning process using the first alignment system 6 is performed when the substrate P is not exposed. The light cleaning process can be executed, for example, for each lot. A lot includes a group of a plurality of substrates P exposed using the same mask M. In the present embodiment, the mask M is placed on the first holding unit 17 of the mask stage 1 before the exposure of the first substrate P (the first substrate P of the lot) among the plurality of substrates P included in the lot is started. The optical cleaning process is executed in the held state. The above-described baseline measurement is also performed at the beginning of the lot.

  Note that the light cleaning process may be executed, for example, every time the exposure process for a predetermined number of substrates P is completed. For example, the optical cleaning process may be executed a plurality of times when the substrate P is not exposed in the same lot.

  Moreover, it is not necessary to perform all the optical cleaning of the measuring members C1, C2, and C3 every time. For example, at the head of the lot, all the optical cleaning of the measuring members C1, C2, and C3 may be performed, and only the optical cleaning of the measuring member C3 may be performed before the processing of the lot is completed. Alternatively, for example, the optical cleaning of the measuring members C1 and C2 may be performed at the head of the lot, and only the optical cleaning of the measuring member C3 may be performed before the processing of the lot is completed.

  Further, when it is determined using the first alignment system 6 that the surface of the measurement member C is contaminated, an optical cleaning process using the first alignment system 6 may be performed. The first alignment system 6 can acquire an image (optical image) of the surface of the measurement member C. The control device 8 can observe the state of the surface of the measuring member C using the first alignment system 6 and can control the operation of the first alignment system 6 based on the observation result. Further, when the control device 8 determines that the contamination state (contamination level) of the surface of the measurement member C is within the allowable range based on the observation result of the first alignment system 6, the control device 8 does not execute the light cleaning process. A normal sequence including the exposure processing of the substrate P can be executed. For example, the surface state of the measuring member C is observed using the first alignment system 6 every time the lot head and / or the exposure processing of a predetermined number of substrates P is completed, and the contamination state (contamination level) of the surface of the measuring member C is observed. The optical cleaning using the first alignment system 6 may be executed only when it is not acceptable.

  Moreover, after irradiating the measuring member C with the detection light LA for optical cleaning, the control device 8 acquires an image of the measuring member C with the first alignment system 6, and the surface state (light) of the measuring member C is obtained. The cleaning effect can be confirmed.

  In addition to the first alignment system 6, an observation device capable of observing the surface state of the measurement member C (for example, an image of the surface can be acquired) is provided, and the measurement member C is configured based on the observation result of the observation device. It can be determined whether or not the surface is subjected to light cleaning, and / or the state of the surface of the measuring member C after light cleaning can be confirmed based on the observation result of the observation device. In the present embodiment, the second alignment system 7 includes an image sensor (CCD), and can acquire an image (optical image) of the surface of the measurement member C. Therefore, the second alignment system 7 may be used as the observation device.

  Note that the observation device for observing whether or not the surface of the measurement member C is optically cleaned may be different from the observation device for checking the state of the surface of the measurement member C after optical cleaning.

  Further, the observation device for observing the first region on the surface of the measuring member C may be different from the observation device for observing the second region. For example, the region including the first reference mark FM1 of the measurement member C3 may be observed with the first alignment system 6, and the region including the second reference mark FM2 may be observed with the second alignment system 7.

  Further, the observation apparatus is not limited to an apparatus that can acquire an image of the surface of the measurement member C.

  In the present embodiment, the timer 9 measures the irradiation time of the detection light LA on the surface of the measurement member C. In this embodiment, the irradiation time (integrated time) of the detection light LA on the surface of the measurement member C3 is the irradiation time of the detection light LA irradiated on the surface of the measurement member C3 for light cleaning, and the baseline measurement. It includes the integrated value of the irradiation time of the detection light LA that is irradiated onto the surface of the measurement member C3 for (position measurement operation of the projection image of the projection optical system PL). As described above, in the present embodiment, the surface of the measurement member C3 is formed of a liquid repellent film. It is effective to irradiate the detection light LA for optical cleaning of the measuring member C3. On the other hand, when the irradiation time of the detection light LA becomes long, the liquid repellency of the liquid repellent film with respect to the liquid LQ may be lowered. When the liquid repellency of the liquid repellent film is lowered, there may be a problem that the liquid LQ tends to remain on the surface of the measuring member C3, for example. In the present embodiment, the control device 8 uses the timer 9 to manage the irradiation time of the detection light LA on the measurement member C3. In the present embodiment, the storage device 8M includes the irradiation time of the detection light LA on the measurement member C3 and the contact angle of the liquid repellent film with respect to the liquid LQ according to the irradiation time (the liquid repellency of the liquid repellent film according to the irradiation time). The degree of decrease) is stored in advance. The relationship can be obtained in advance by preliminary experiments or simulations. For example, when the control device 8 determines that the liquid repellency of the liquid repellent film is equal to or lower than a predetermined allowable level based on the storage information of the storage device 8M and the measurement result of the timer 9, the measurement member C3 Execute the maintenance process. In the present embodiment, the replacement work of the measurement member C3 is performed. Thereby, the measurement member C3 having a desired liquid-repellent surface is disposed on the measurement stage 3.

  In the present embodiment, the control device 8 also uses the timer 9 to calculate the irradiation time of the detection light LA on the surfaces of the measurement members C1 and C2 and the irradiation time of the exposure light EL on the surfaces of the measurement members C1 and C2. to manage. As a result, like the measurement member C3, the measurement members C1 and C2 can be maintained (replaced) before the liquid repellency of the surfaces of the measurement members C1 and C2 falls below an allowable level.

  As described above, according to the present embodiment, the first alignment system 6 is used to optically wash the surface of a member disposed on the image plane side of the projection optical system PL via the projection optical system PL. be able to. Therefore, the occurrence of defective exposure and the occurrence of defective devices can be suppressed.

  In the above-described embodiment, the case where the detection light LA is irradiated to the member on the image plane side through the transmission part 16 of the optical member 15 disposed on the mask stage 1 and the projection optical system PL is taken as an example. As described above, for example, when at least a part of the mask M is provided with a transmission part capable of transmitting the detection light LA, the projection optical system passes through the transmission part of the mask M and the projection optical system PL. The member arranged on the image plane side of the PL may be irradiated with the detection light LA, and the surface of the member may be optically cleaned. For example, as shown in FIG. 9, a transmission part 80 capable of transmitting the detection light LA is provided at a predetermined position in a light shielding region of a mask M different from the pattern region MA where the pattern is formed. The first alignment system 6 is a member disposed on the image plane side of the projection optical system PL via the transmission unit 80 of the mask M held on the mask stage 1 (first holding unit 17) and the projection optical system PL. The surface can be irradiated with detection light LA. Further, before the mask M is held on the mask stage 1, the detection light LA may be irradiated to the surface of a member arranged on the image plane side of the projection optical system PL via the opening 71 and the opening 73.

  In the above-described embodiment, an example is given in which the liquid LQ is held between the projection optical system PL (terminal optical element 21) and the member to be cleaned, and the member is irradiated with the detection light LA. As described above, in a state where the liquid LQ is not held, that is, in a state where the member to be optically cleaned and the liquid LQ are not in contact, the member to be optically cleaned is irradiated with the detection light LA to perform optical cleaning. May be.

  Alternatively, the optical cleaning may be performed in a state where the space between the projection optical system PL (terminal optical element 21) and the optical cleaning target member is filled with a liquid different from the exposure liquid LQ.

  In the above-described embodiment, the first alignment system 6 is an image type alignment system. However, the first alignment system 6 is not limited to the image type, and is, for example, an alignment system as disclosed in US Pat. No. 4,655,598. May be.

  Further, in the above-described embodiment, the first alignment system 6 irradiates the measurement member C3 disposed on the image plane side of the projection optical system PL with the detection light LA from the emission unit 6A and from the measurement member C3. Is received by the detection unit 6B via the projection optical system PL. At least a part of the detection unit of the first alignment system 6 is provided on the measurement stage 3, and the measurement member C3 irradiated with the detection light LA is used. The light may be received by the detection unit without passing through the projection optical system PL. For example, similarly to the above-described embodiment, the detection light LA may be applied to the light transmission part provided in the measurement member C3, and the light from the light transmission part may be received by the detection part.

  In the above-described embodiment, the measurement members C1, C2, and C3 are mounted on the measurement stage 3. However, at least a part of the measurement members C1, C2, and C3 may be mounted on the substrate stage 2. In this case, the exposure apparatus EX may not include the measurement stage 3.

  Moreover, in the above-mentioned embodiment, although optical cleaning is performed using the detection light LA of the first alignment system 6, optical cleaning using the exposure light EL may be used in combination.

  In the above-described embodiment, the optical path on the exit side (image plane side) of the terminal optical element 21 of the projection optical system PL is filled with the liquid LQ, but is disclosed in, for example, International Publication No. 2004/019128 Pamphlet. As described above, it is possible to employ a projection optical system in which the optical path on the incident side (object plane side) of the last optical element 21 is also filled with the liquid LQ.

  In addition, although the liquid LQ of each above-mentioned embodiment is water, liquids other than water may be sufficient. For example, hydrofluoroether (HFE), perfluorinated polyether (PFPE), fomblin oil, or the like can be used as the liquid LQ. In addition, various fluids such as a supercritical fluid can be used as the liquid LQ.

  The exposure apparatus EX of the above-described embodiment employs a local immersion method in which only a part of the region on the substrate P is covered with the liquid LQ during the exposure of the substrate P. In the exposure apparatus EX, During the exposure of the substrate P, the entire surface (exposure surface) of the substrate P may be covered with the liquid LQ.

  Further, the exposure apparatus EX may be a non-immersion type exposure apparatus that irradiates the substrate P with the exposure light EL without using a liquid.

  As the substrate P in each of the above embodiments, 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.

  Furthermore, in the step-and-repeat exposure, after the reduced image of the first pattern is transferred onto the substrate P using the projection optical system while the first pattern and the substrate P are substantially stationary, the second pattern With the projection optical system, the reduced image of the second pattern may be partially overlapped with the first pattern and collectively exposed on the substrate P (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.

  Also, the requirements of the above-described embodiments are that, for example, as disclosed in the corresponding US Pat. No. 6,611,316, two mask patterns are synthesized on a substrate via a projection optical system, and The present invention can also be applied to an exposure apparatus that double exposes one shot area on a substrate almost simultaneously by scanning exposure. The requirements of the above-described embodiments can also be applied to proximity-type exposure apparatuses, mirror projection aligners, and the like.

  In addition, the requirements of the above-described embodiments are that a multi-stage including a plurality of substrate stages as disclosed in US Pat. No. 6,341,007, US Pat. No. 6,208,407, US Pat. It can also be applied to a stage type exposure apparatus. Three or more substrate stages can be arranged.

  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). ), An exposure apparatus for manufacturing a micromachine, a MEMS, a DNA chip, a reticle, a mask, or the like.

  In each of the above-described embodiments, a light-transmitting mask in which a predetermined light-shielding pattern (or phase pattern / dimming pattern) is formed on a light-transmitting substrate is used. As disclosed in Japanese Patent No. 6778257, a variable shaped mask (also known as an electronic mask, an active mask, or an image generator) that forms a transmission pattern, a reflection pattern, or a light emission pattern based on electronic data of a pattern to be exposed. May be used). The variable shaping mask includes, for example, a DMD (Digital Micro-mirror Device) which is a kind of non-light emitting image display element (spatial light modulator). Further, a pattern forming apparatus including a self-luminous image display element may be provided instead of the variable molding mask including the non-luminous image display element. As a self-luminous type image display element, for example, CRT (Cathode Ray Tube), inorganic EL display, organic EL display (OLED: Organic Light Emitting Diode), LED display, LD display, field emission display (FED: Field Emission Display) And a plasma display panel (PDP).

  In each of the above embodiments, the exposure apparatus provided with the projection optical system PL has been described as an example. However, the exposure apparatus EX may not include the projection optical system PL.

  The exposure apparatus EX exposes a line-and-space pattern on the substrate P by forming interference fringes on the substrate P as disclosed in, for example, WO 2001/035168. It may be an apparatus (lithography system).

  As described above, the exposure apparatus EX of 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. 10, 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 substrate of the device. Manufacturing step 203, substrate processing step 204 including exposing the substrate with an exposure beam using a pattern of a mask and developing the exposed substrate according to the above-described embodiment, device assembly step (dicing process, (Including processing processes such as a bonding process and a packaging process) 205, an inspection step 206, and the like.

  Note that the requirements of the above-described embodiments can be combined as appropriate. Some components may not be used. In addition, as long as permitted by law, the disclosure of all published publications and US patents related to the exposure apparatus and the like cited in the above-described embodiments and modifications are incorporated herein by reference.

It is a schematic block diagram which shows an example of the exposure apparatus which concerns on this embodiment. It is a perspective view which shows an example of the liquid immersion member which concerns on this embodiment. It is a top view which shows an example of the substrate stage and measurement stage which concern on this embodiment. It is a sectional side view which shows an example of the measuring member which concerns on this embodiment. It is a sectional side view which shows the vicinity of the mask stage which concerns on this embodiment. It is a top view which shows the positional relationship of the mask stage and 1st alignment system which concern on this embodiment. It is a figure which shows an example of operation | movement of the exposure apparatus which concerns on this embodiment. It is a figure for demonstrating the operation | movement which concerns on the optical cleaning process which concerns on this embodiment. It is a top view which shows an example of the mask which concerns on this embodiment. It is a flowchart for demonstrating an example of the manufacturing process of a microdevice.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mask stage, 6 ... 1st alignment system, 7 ... 2nd alignment system, 9 ... Timer, 15 ... Optical member, 16 ... Transmission part, 53 ... Liquid-repellent film, 80 ... Transmission part, C ... Measurement member, EL ... exposure light, EX ... exposure device, FM1 ... first reference mark, FM2 ... second reference mark, FM3 ... third reference mark, LA ... detection light, LQ ... liquid, LS ... immersion space, M ... mask, MA ... Pattern area, P ... Substrate, PL ... Projection optical system

Claims (16)

An exposure apparatus that exposes the substrate by irradiating the substrate with exposure light via a projection optical system,
At least a portion is disposed on the object plane side of the projection optical system, and the first reference mark disposed on the image plane side of the projection optical system is irradiated with detection light via the projection optical system, thereby A first detection device capable of detecting a reference mark;
The first detection apparatus is an exposure apparatus that irradiates a predetermined member disposed on the image plane side via the projection optical system with the detection light and performs optical cleaning on the predetermined member when the substrate is not exposed. The first detection device detects the first reference mark via a first alignment mark arranged on the object plane side and the projection optical system, and acquires position information of a projection image by the projection optical system. Is possible,
2. The exposure apparatus according to claim 1, wherein when the predetermined member is optically cleaned, the first detection device irradiates the predetermined member with the detection light without passing through the first alignment mark. An optical member disposed on the object plane side and having a transmission part capable of transmitting the detection light;
3. The exposure apparatus according to claim 2, wherein the first detection device irradiates the predetermined member with the detection light via the transmission unit and the projection optical system during the optical cleaning of the predetermined member.   The exposure apparatus according to claim 3, wherein the first alignment mark is disposed at a predetermined position of the optical member different from the transmission portion. A mask stage that is movable on the object plane side while holding a mask on which a pattern projected onto the substrate by the projection optical system is formed;
The exposure apparatus according to claim 3, wherein the optical member is disposed on the mask stage. On the object plane side, a mask on which a pattern for projection onto the substrate is formed by the projection optical system is disposed,
The mask has a transmission part capable of transmitting the detection light at a position different from a pattern region where the pattern is formed,
3. The exposure apparatus according to claim 2, wherein the first detection device irradiates the predetermined member with the detection light via the transmission unit and the projection optical system during the optical cleaning of the predetermined member.   The exposure apparatus according to claim 1, wherein the predetermined member includes a reference member on which the first reference mark is arranged.   The exposure apparatus according to claim 1, wherein the predetermined member includes a measurement member that measures the exposure light irradiated to the image plane side of the projection optical system. The substrate is exposed via the projection optical system and the liquid;
The exposure apparatus according to claim 1, wherein the liquid is held between the projection optical system and the predetermined member during the optical cleaning of the predetermined member. An observation device capable of observing the state of the surface of the predetermined member;
The exposure apparatus according to claim 1, wherein an operation of the first detection apparatus is controlled based on an observation result of the observation apparatus. A second alignment mark arranged on the substrate and a second reference mark arranged on the image plane side in a predetermined positional relationship with the first reference mark can be obtained without using the projection optical system. Equipped with a detection device,
The exposure apparatus according to claim 10, wherein the observation apparatus includes the second detection apparatus. The surface of the predetermined member irradiated with the detection light is formed of a liquid repellent film,
The exposure apparatus according to claim 1, further comprising a measuring device that measures an irradiation time of the detection light on the surface of the predetermined member. Exposing the substrate using the exposure apparatus according to any one of claims 1 to 12,
Developing the exposed substrate; and a device manufacturing method. An exposure method for exposing the substrate by irradiating the substrate with exposure light via a projection optical system,
Using the first detection device at least a part of which is disposed on the object plane side of the projection optical system, detection light is transmitted to the first reference mark disposed on the image plane side of the projection optical system via the projection optical system. And detecting the first fiducial mark;
Adjusting the position of the substrate using position information of a projection image obtained by the projection optical system acquired based on the detection result, and exposing the substrate;
Irradiating the predetermined member disposed on the image plane side through the projection optical system with the detection light when the substrate is not exposed, and optically washing the predetermined member. An exposure method comprising: The substrate is exposed via the projection optical system and the liquid;
The exposure method according to claim 14, wherein the predetermined member is subjected to optical cleaning by irradiating the predetermined member with the detection light through a liquid between the projection optical system and the predetermined member. Exposing the substrate using the exposure method according to claim 14 or 15,
Developing the exposed substrate; and a device manufacturing method.

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