Determination method, adjustment method, and article manufacturing method

Abstract

To provide a technique advantageous for making adjustment of an exposure apparatus easier in a transfer destination having a different environment from a place before transfer.SOLUTION: A determination method for determining an adjustment amount of an exposure apparatus having a projection optical system in the case of transferring the exposure apparatus from a first environment to a second environment includes: a measurement step of measuring optical performance in the first environment regarding the projection optical system of a reference state to which a first optical component having a first light-transmitting member is attached; an estimation step of estimating optical performance in the second environment regarding the projection optical system of the reference state to which a second optical component having a second light-transmitting member with a different thickness from the first light-transmitting member; and a determination step of determining an inclination amount of the second light-transmitting member in installing the second optical component to the projection optical system in the second environment such that a difference between the optical performance measured in the measurement step and the optical performance estimated in the estimation step is reduced.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to a determination method for determining an adjustment amount of an exposure apparatus, an adjustment method of an exposure apparatus, and an article manufacturing method.

Background Art

[0002] In a lithography process which is a manufacturing process of semiconductor devices and MEMS devices, an exposure apparatus having a projection optical system is used. In the exposure apparatus, since the optical performance of the projection optical system can change in conjunction with fluctuations in the external environment, it is disposed in a constant temperature chamber in which the temperature and humidity are controlled within a semiconductor device factory. However, it is difficult to accurately control the air pressure in the constant temperature chamber. Therefore, the exposure apparatus is provided with a correction mechanism for correcting the optical performance of the projection optical system, and the optical performance of the projection optical system can be corrected according to fluctuations in air pressure by the correction mechanism. Patent Document 1 discloses a technique for correcting the optical performance (magnification) of a projection optical system by displacing a lens in the projection optical system in the optical axis direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The environment (e.g., altitude, atmospheric pressure) at the destination (shipment destination) where the exposure apparatus is installed may be different from the environment at the location before relocation (before shipment) where the exposure apparatus is manufactured, such as when a projection optical system is installed in the exposure apparatus. In this case, a difference may occur in the optical performance of the projection optical system between the location before relocation and the destination. As a method for reducing such a difference in optical performance, there is a method of replacing optical components attached to the projection optical system. However, just replacing the optical components may not satisfy the desired specifications for the optical performance of the projection optical system at the destination, and adjustments such as tilting the optical components with respect to the projection optical system may be required when attaching the optical components to the projection optical system.

[0005] Therefore, an object of the present invention is to provide an advantageous technique for facilitating the adjustment of an exposure apparatus at a destination where the environment is different from that before relocation.

Means for Solving the Problems

[0006] In order to achieve the above object, a determination method according to one aspect of the present invention is a determination method for determining an adjustment amount of the exposure apparatus when the exposure apparatus having a projection optical system is relocated from a first environment to a second environment, including: a measurement step of measuring the optical performance in the first environment for the projection optical system in a reference state in which a first optical component having a first light transmission member is attached; an estimation step of estimating the optical performance in the second environment for the projection optical system in the reference state in which a second optical component having a second light transmission member with a different thickness from the first light transmission member is attached; and a determination step of determining an inclination amount of the second light transmission member when attaching the second optical component to the projection optical system in the second environment so that the difference between the optical performance measured in the measurement step and the optical performance estimated in the estimation step is reduced, wherein the projection optical system includes a lens and a drive mechanism for driving the lens, and the reference state is a state in which the lens is disposed at a reference position within a stroke range in which the lens can be driven by the drive mechanism.

[0007] A further object or other aspect of the present invention will be clarified by the preferred embodiments described below with reference to the accompanying drawings.

Advantages of the Invention

[0008] According to the present invention, for example, it is possible to provide an advantageous technique for facilitating the adjustment of an exposure apparatus at a relocation destination where the environment is different from that before relocation.

Brief Description of the Drawings

[0009]

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MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential for the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0011] <First Embodiment> The first embodiment according to the present invention will be described. The exposure apparatus is a lithography apparatus used in a lithography process which is a manufacturing process of devices such as semiconductor elements, liquid crystal display elements, and magnetic storage media as articles. The exposure apparatus performs an exposure process of exposing a substrate through a reticle and transferring (forming) a pattern formed on the reticle onto the substrate.

[0012] The exposure apparatus adopts a step-and-repeat method or a step-and-scan method, and while moving the substrate step by step, sequentially transfers the pattern of the reticle to a plurality of regions (shot regions) of the substrate. An exposure apparatus that performs the transfer of the reticle pattern all at once is called a stepper, and an exposure apparatus that performs the transfer of the reticle pattern while relatively scanning (scanning) the reticle and the substrate is called a scanner. Note that the basic operation of transferring the reticle pattern to the substrate while moving the substrate step by step is common to both the stepper and the scanner. In addition, the exposure apparatus can use, for example, i-line with a wavelength of 365 nm, KrF excimer laser with a wavelength of 248 nm, ArF excimer laser with a wavelength of 193 nm, extreme ultraviolet light (EUV) with a wavelength of several nm to several hundred nm, etc. as the exposure light (exposure wavelength).

[0013] FIG. 1 is a schematic diagram showing a configuration example of the exposure apparatus EXP of the present embodiment. As shown in FIG. 1, the exposure apparatus EXP includes an illumination optical system 3 that illuminates a reticle 6 with light 2 from a light source 1, and a reticle stage 7 that holds the reticle 6. Further, the exposure apparatus EXP includes a projection optical system 8 that projects the pattern of the reticle 6 onto a substrate 9, a substrate stage 11 that holds the substrate 9, and a control unit CU.

[0014] Light 2 (exposure light) in a predetermined wavelength range emitted from the light source 1 enters the illumination optical system 3, is guided to a condenser lens 5 via a mirror 4, and illuminates the pattern (pattern surface) of the reticle 6 with uniform illuminance. The illumination optical system 3 may be provided with a measuring instrument that measures the integrated light amount (exposure amount) of the light 2 irradiated onto the substrate 9.

[0015] The original reticle 6 is transported by a reticle transport device (not shown) to a predetermined position within the exposure apparatus (specifically, on the reticle stage 7) and held (suction-fixed) by the reticle stage 7. The light 2 that has passed through the reticle 6 is incident on the projection optical system 8. The projection optical system 8 projects an image of the pattern of the reticle 6 onto a predetermined area (one shot area) of the substrate 9. Here, an adjustment spacer 7SP for adjusting the position and orientation of the surface (object surface) of the reticle is arranged at the fixing portion of the reticle stage 7. Also, the position of the reticle stage 7 is measured at any time by a measuring device including a laser interferometer and a moving mirror, and is controlled (positioned) by the control unit CU.

[0016] The substrate 9 is held by the substrate stage 11 via the chuck 10. The position of the substrate stage 11 is measured at any time by a measuring device including a laser interferometer and a moving mirror, and is controlled (positioned) by the control unit CU. When the exposure apparatus EXP is a scanner, the movement (scanning) of the reticle stage 7 and the movement (scanning) of the substrate stage 11 are synchronously controlled by the control unit CU. Here, one or more reference substrates 14 are fixedly provided on the chuck 10 or in the vicinity of the chuck 10 on the substrate stage 11. The reference substrate 14 is arranged such that its surface (upper surface) is substantially at the same height as the upper surface of the substrate 9. A plurality of reference marks formed of Cr, Al, etc. are provided on the surface of the reference substrate 14.

[0017] Also, the exposure apparatus EXP may include a surface position detection unit 12 for detecting the position (height) of the surface of the substrate 9 (or the surface of the reference substrate 14) and an alignment scope 13 (alignment detection unit) for detecting alignment marks provided on the substrate 9 (or the reference substrate 14).

[0018] The surface position detection unit 12 employs an oblique incidence type position detection method. The surface position detection unit 12 irradiates non-exposed light obliquely onto the surface of the substrate 9 (or the reflection surface of the reference substrate 14) where the pattern of the original plate 6 is transferred by the projection optical system 8, and detects the reflected light that is reflected obliquely from the surface of the substrate 9 (or the surface of the reference substrate 14). The surface position detection unit 12 has light receiving elements for position detection corresponding individually to one or more light beams reflected from the surface of the substrate 9 (or the surface of the reference substrate 14), and is arranged such that the light receiving surface of the light receiving element and the surface of the substrate 9 (the reflection point of each light beam) are substantially conjugate. Therefore, the displacement of the substrate 9 (or the reference substrate 14) in the optical axis direction of the projection optical system 8 is measured as the displacement of the reflected light on the light receiving surface of the light receiving element. Further, an adjustment spacer 12SP for adjusting the focal position of the surface position detection unit 12 to the height of the surface of the substrate 9 during the manufacture of the exposure apparatus EXP is provided in the fixing portion of the surface position detection unit 12.

[0019] The alignment scope 13 has a scope reference mark inside thereof. The alignment marks provided on the substrate 9 or the reference substrate 14 are arranged within the detection range (detection visual field) of the alignment scope 13 by driving the substrate stage 11. Then, the alignment scope 13 measures the relative displacement amount between the alignment mark provided on the substrate 9 or the reference substrate 14 and the scope reference mark. Based on the measurement result, the control unit CU can perform alignment and baseline correction of the substrate 9. Further, an adjustment spacer 13SP for adjusting the focal position of the alignment scope 13 to the height of the surface of the substrate 9 during the manufacture of the exposure apparatus EXP is provided in the fixing portion of the alignment scope 13.

[0020] A wavefront measurement unit 15 is provided below the reference substrate 14. The wavefront measurement unit 15 measures the aberration of the projection optical system 8 generated on the reference substrate 14. The measurement result of the aberration of the projection optical system 8 by the wavefront measurement unit 15 is transmitted to the control unit CU.

[0021] The control unit CU is composed of a computer (information processing device) including a processor such as a CPU (Central Processing Unit) and a storage unit such as a memory. The control unit CU comprehensively controls each part of the exposure apparatus EXP according to a program stored in the storage unit or the like to operate the exposure apparatus EXP. The control unit CU controls an exposure process for transferring the pattern of the reticle 6 onto the substrate 9 and various processes related to the exposure process.

[0022] Next, the adjustment of the exposure apparatus EXP (projection optical system 8) in the present embodiment will be described. FIG. 2 is a diagram for explaining the adjustment of the projection optical system 8. As shown in FIG. 2, the projection optical system 8 includes a lens 8a and a drive mechanism 8b that drives the lens 8a in the optical axis direction (Z direction) along the optical axis of the projection optical system 8. By driving the lens 8a in the optical axis direction by the drive mechanism 8b, the optical performance (for example, aberration) of the projection optical system 8 can be corrected. Here, in the specification and the accompanying drawings, the optical axis direction along the optical axis of the projection optical system 8 is defined as the Z direction (first direction), and two directions perpendicular to the Z direction and perpendicular to each other are defined as the X and Y directions (second direction). Also, the rotations around the X axis, Y axis, and Z axis are respectively denoted as ωx, ωy, and ωz.

[0023] As shown in FIG. 3, the drive mechanism 8b of the projection optical system 8 also drives the position of the lens 8a in the lens adjustment process, the apparatus mounting process, and the transportation and installation process. In FIG. 3, the lens adjustment process is a process of adjusting the position of the lens 8a in the projection optical system 8. The apparatus mounting process is a process of mounting the projection optical system 8 that has undergone the lens adjustment process on the exposure apparatus EXP. The transportation and installation process is a process of transporting and installing the exposure apparatus EXP that has undergone the apparatus mounting process to the relocation destination (shipping destination). The device manufacturing process is a process of actually performing an exposure process on the exposure apparatus EXP installed through the transportation and installation process to manufacture a device.

[0024] In each process, the stroke by which the drive mechanism 8b can drive the lens 8a can be managed within the stroke budget (within the stroke range) set during development. Even if the adjustment position of the lens 8a is offset within the stroke budget from the lens adjustment process to the transportation and installation process, the stroke available for device manufacturing is budgeted as an upper stroke and a lower stroke as the device manufacturing stroke.

[0025] Here, in the exposure apparatus EXP, it is desirable that the optical performance of the projection optical system 8 satisfies the desired specifications in the state (reference state) where the lens 8a is arranged at the lens design position (reference position) within the stroke budget. The lens design position (reference position) can be set, for example, at a position that is the midpoint between the upper limit and the lower limit of the stroke budget (stroke range). In this case, the distance from the lens design position to the upper limit of the stroke budget (upper stroke) and the distance from the lens design position to the lower limit of the stroke budget (lower stroke) are made the same, and the position of the lens 8a can be appropriately adjusted according to changes in the external environment.

[0026] However, the external environment (the second environment) of the transfer destination where the transportation and installation process and the device manufacturing process are performed may be different from the external environment (the first environment) before transfer where the lens adjustment process and the device mounting process are performed. For example, the elevation of the transfer destination where the transportation and installation process and the device manufacturing process are performed may be different from the elevation of the location before transfer where the lens adjustment process and the device mounting process are performed. Therefore, it becomes newly necessary to consider the change in the optical performance of the projection optical system 8 due to the elevation difference (atmospheric pressure difference). When the change in the optical performance of the projection optical system 8 is addressed by driving the lens 8a of the projection optical system 8 with the drive mechanism 8b, as shown in FIG. 4, the position of the lens 8a at which the optical performance of the projection optical system 8 can satisfy the desired specifications deviates from the lens design position (reference position). That is, the central position of the lens 8a in the stroke budget table moves, and the upper stroke and the lower stroke change. Since the upper and lower limits of the stroke budget are fixed with respect to the position of the lens 8a before the lens adjustment process, when the external environment changes, for example, as shown in FIG. 4, the upper stroke narrows, and there is a problem that the upper stroke available in the device manufacturing process is insufficient. As a result, when using the device manufacturing recipe determined in the external environment before relocation (for example, low elevation) at the relocation destination (for example, high elevation), there may arise a problem that the upper stroke becomes insufficient. That is, there may arise a problem that the device manufacturing recipe established in the external environment before relocation cannot be used in the external environment of the relocation destination.

[0027] Therefore, an optical component (optical unit) for correcting the optical performance of the projection optical system 8 is attached to the projection optical system 8 of the exposure apparatus EXP of the present embodiment. The optical component is attached (externally attached) to the projection optical system 8, for example, at the lower part of the projection optical system 8, that is, so as to be disposed in the optical path of the light emitted from the projection optical system 8.

[0028] In the exposure apparatus EXP of the present embodiment, as shown in FIG. 2, a plurality of optical components that can be replaced with respect to the projection optical system 8 are prepared (stocked, accommodated) even after the completion of the assembly of the exposure apparatus EXP. Hereinafter, as the plurality of optical components, the first optical component UnitA and the second optical component UnitB will be exemplified and described, but the number of optical components is not limited to two, and may be three or more.

[0029] The first optical component UnitA has a plurality of first light transmissive members. In the case of the present embodiment, the plurality of first light transmissive members may include two transparent planar glasses 22, 23 (glass plates) having substantially the same refractive index and thickness. The planar glasses are not limited to two, and may be three or more as long as the number, thickness, and refractive index that can be tilted in opposite directions are equal to each other. The first optical component UnitA can be used when the difference between the external environment (first environment) of the assembly location and the external environment (second environment) of the installation location is within a threshold value that can satisfy the optical performance specifications of the exposure apparatus EXP (projection optical system 8). Note that the assembly location is the location where the projection optical system 8 and the exposure apparatus EXP are assembled, and is the location before the relocation of the exposure apparatus EXP. The installation location is the location where the exposure apparatus EXP is installed and operated, and is the relocation destination of the exposure apparatus EXP. The external environment may include, for example, the altitude (atmospheric pressure) of the location.

[0030] The second optical component UnitB has a plurality of second light-transmitting members. In the case of this embodiment, the plurality of second light-transmitting members may include two transparent planar glasses 24 and 25 (glass plates) having substantially the same refractive index and thickness. The planar glasses are not limited to two, and may be three or more as long as the number, thickness, and refractive index that can be tilted in opposite directions to each other are equal. The planar glasses 24 and 25 of the second optical component UnitB have different thicknesses in the optical axis direction so as to correct the optical performance of the projection optical system 8 due to environmental differences (elevation difference, air pressure difference) between the assembly location and the installation location compared to the planar glasses 22 and 23 of the first optical component UnitA. The second optical component UnitB can be used when the environmental difference (elevation difference, air pressure difference) between the assembly location and the installation location exceeds the threshold value that can establish the optical performance specifications of the exposure apparatus EXP (projection optical system 8). For the second optical component UnitB, planar glasses with different thicknesses are prepared according to the environment (elevation) of the installation location.

[0031] In addition, the first optical component UnitA includes a first change mechanism for mechanically changing the inclination of each of the plurality of first light-transmitting members (two planar glasses 22 and 23). Similarly, the second optical component UnitB includes a second change mechanism for mechanically changing the inclination of each of the plurality of second light-transmitting members (two planar glasses 24 and 25). Hereinafter, a configuration example of the optical component will be described. Since the first change mechanism of the first optical component UnitA and the second change mechanism of the second optical component UnitB may have the same configuration, the configuration example of the second optical component UnitB will be described here.

[0032] FIG. 5 is a schematic diagram showing a configuration example 1 of the second optical component UnitB. FIGS. 5(a) to 5(b) show the postures (postures with respect to the optical axis of the projection optical system 8) of the two planar glasses 24 and 25 in the second optical component UnitB. FIG. 5(a) shows the state before changing the postures of the planar glasses 24 and 25, and FIG. 5(b) shows the state after changing the postures of the planar glasses 24 and 25.

[0033] The flat glass 24 is held (fixed) by the first holding part 20 (first holding member 26). The flat glass 25 is held (fixed) by the second holding part 21 (second holding member 27). Since the holding structures of the flat glass in the first holding part 20 and the second holding part 21 are the same, here, a configuration example of the first holding part 20 will be described. FIG. 6 is a schematic diagram showing a configuration example of the first holding part 20 that holds the flat glass 24. FIG. 6(a) is a view of the first holding part 20 seen from above (+Z direction), and FIG. 6(b) is a view of the pressing ring 28 attached to the first holding member 26 seen from above (+Z direction). FIG. 6(c) is a view of the first holding member 26 with the pressing ring 28 attached seen from the side (+X direction).

[0034] The flat glass 24 is mounted on the protrusion 26a (protrusion surface) of the first holding member 26. The protrusions 26a are arranged, for example, at three positions on the circumference outside the exposure beam diameter at a 120° pitch. The pressing ring 28 has protrusions 28a (protrusion surfaces) at three positions facing the protrusions 26a of the first holding member 26 through the flat glass 24. Also, an annular leaf spring 29 for biasing the pressing ring 28 is provided on the upper surface of the first holding member 26. The flat glass 24 is held by the first holding part 20 by being sandwiched between the first holding member 26 (protrusion 26a) and the pressing ring 28 (protrusion 28a) by the action of the leaf spring 29. Here, the holding of the flat glass 24 by the first holding part 20 is not limited to using the pressing ring 28 and the leaf spring 29, and it can also be performed by adhesively fixing the side surface of the flat glass 24 and the inner surface of the first holding member 26. Also, the holding of the flat glass 25 by the second holding part 21 can be performed by the same method as the holding of the flat glass 24 by the first holding part 20.

[0035] As shown in FIG. 5, the first holding portion 20 and the second holding portion 21 are held by the third holding portion 30. The third holding portion 30 is configured such that the first holding portion 20 and the second holding portion 21 can be rotated respectively about the optical axis of the projection optical system 8. The contact surfaces between the first holding portion 20 and the third holding portion 30 and between the second holding portion 21 and the third holding portion 30 are inclined respectively. Thereby, by individually rotating the first holding portion 20 and the second holding portion 21 with respect to the third holding portion 30, the two planar glasses 24 and 25 can be individually tilted with respect to the optical axis of the projection optical system 8. Further, by rotating the first holding portion 20 and the second holding portion 21 by the same amount with respect to the third holding portion 30, the relative tilt between the planar glass 24 and the planar glass 25 can be changed (adjusted).

[0036] Here, as described above, the first holding portion 20 holds the planar glass 24 by three protrusions 26a arranged at a 120° pitch in the first holding member 26. Similarly, the second holding portion 21 holds the planar glass 25 by three protrusions arranged at a 120° pitch in the second holding member 27. The protrusions 26a of the first holding member 26 in the first holding portion 20 and the protrusions of the second holding member 27 in the second holding portion 21 are offset from each other by 60°. Thereby, it is possible to reduce the aberration generated by the self-weight deformation of the planar glasses 24 and 25 held by the first holding portion 20 and the second holding portion 21 respectively.

[0037] The third holding part 30 is attached to the fourth holding part 31, and the fourth holding part 31 is rotatably attached to the fifth holding part 32. The fifth holding part 32 is attached to the lower part of the projection optical system 8. The fifth holding part 32 may be attached to the lower part of the projection optical system 8 via an adjustment spacer. The contact surface between the fourth holding part 31 and the fifth holding part 32 is inclined, and the fourth holding part 31 is configured to be rotatable with respect to the fifth holding part 32 about the optical axis of the projection optical system 8. By rotating the fourth holding part 31 with respect to the fifth holding part 32, the third holding part 30 connected to the fourth holding part 31 can also be rotated. Thereby, in a state where the relative inclination between the flat glass 24 and the flat glass 25 is maintained, the inclination of the two flat glasses 24 and 25 in the integrated state can be changed (adjusted) with respect to the optical axis of the projection optical system 8. Further, the fifth holding part 32 is configured to be detachable from the projection optical system 8. That is, the optical components attached to the projection optical system 8 can be replaced without removing the projection optical system 8 from the main body of the exposure apparatus EXP.

[0038] The first optical component UnitA and the second optical component UnitB can also use the configuration shown in FIG. 7. FIG. 7 is a schematic diagram showing a second configuration example of the second optical component UnitB. FIGS. 7(a) to 7(b) show the postures (postures with respect to the optical axis of the projection optical system 8) of the two flat glasses 24 and 25 in the second optical component UnitB. FIG. 7(a) shows the state before changing the postures of the flat glasses 24 and 25, and FIG. 7(b) shows the state after changing the postures of the flat glasses 24 and 25. The configuration of the second optical component UnitB shown in FIG. 7 has the same holding structure for the flat glasses 24 and 25 as the configuration of the second optical component UnitB shown in FIG. 5, but the configuration for changing the postures of the first holding part 20 and the second holding part 21 is different. Note that the first holding component UnitA can have the same configuration as the second optical component UnitB.

[0039] The planar glass 24 is held (fixed) by the first holding part 20 (first holding member 33). The first holding member 33 of the first holding part 20 has the same configuration as the aforementioned first holding member 26. The first holding part 20 is held by the third holding part 36 via an angle changing mechanism 35. The angle changing mechanism 35 can be arranged at three positions shifted by 60° with respect to the protrusions of the first holding member 33 that holds the planar glass 24 in order to reduce the influence of the force generated when the first holding part 20 (first holding member 33) is held by the third holding part 36 on the planar glass 24. Further, an elastic hinge or a spherical washer may be provided at the fixing part of the first holding part 20 to reduce the influence of distortion or the like on the planar glass 24 when the first holding part 20 is held by the third holding part 36 in an inclined state.

[0040] The planar glass 25 is held (fixed) by the second holding part 21 (second holding member 34). The second holding member 34 of the second holding part 21 has the same configuration as the aforementioned second holding member 27. The second holding part 21 is held by the third holding part 36 via an angle changing mechanism 37. The angle changing mechanism 37 can be arranged at three positions shifted by 60° with respect to the protrusions of the second holding member 34 that holds the planar glass 25 in order to reduce the influence of the force generated when the second holding part 21 (second holding member 34) is held by the third holding part 36 on the planar glass 25. Further, an elastic hinge or a spherical washer may be provided at the fixing part of the second holding part 21 to reduce the influence of distortion or the like on the planar glass 25 when the second holding part 21 is held by the third holding part 36 in an inclined state.

[0041] The three protrusions of the first holding member 33 that hold the planar glass 24 and the three protrusions of the second holding member 34 that hold the planar glass 25 may be provided on the third holding part 36 with a 60° shift from each other. Thereby, the influence of the self-weight deformation of the planar glass 24 and the planar glass 25 can be reduced.

[0042] Here, the optical component of Configuration Example 1 is a method of tilting both the first holding portion 20 and the second holding portion 21 with respect to the optical axis of the projection optical system 8. On the other hand, in the optical component of Configuration Example 2, after tilting either the first holding portion 20 or the second holding portion 21 with respect to the optical axis of the projection optical system 8, the other is tilted by the same amount in the direction opposite to the tilting direction of the one. The angle changing mechanisms 35 and 37 in the optical component of Configuration Example 2 can be structured to change the tilt by the difference in the thickness of the adjustment spacers, or to change the tilt by the difference in the protruding amount of the press screws. Further, the angle changing mechanisms 35 and 37 may be structured to adjust the tilt by driving with a driving element such as a piezo element, or to change the tilt with a driving mechanism composed of a combination of a driving element and an elastic hinge that converts the magnification of the applied force or the direction of the applied force.

[0043] Next, an example of the posture change flow of the planar glass 24 and 25 in the optical component of Configuration Example 2 will be described. In advance, the necessary tilt amounts with respect to the planar glass 24 and 25 are measured or calculated. First, the first holding portion 20 is tilted with respect to the optical axis of the projection optical system 8 by the angle changing mechanism 35. Next, the second holding portion 21 is tilted by the same amount in the direction opposite to the first holding portion 20 by the angle changing mechanism 37. Finally, similar to the optical component of Configuration Example 1, the fourth holding portion 31 is rotated with respect to the fifth holding portion 32 attached to the projection optical system 8, and the two planar glass 24 and 25 are tilted as a unit with respect to the optical axis of the projection optical system 8.

[0044] FIG. 8 is a diagram for explaining the stroke budget when using optical components. In the present embodiment, a plurality of optical components (first optical component UnitA, second optical component UnitB) are stocked in the exposure apparatus EXP, and the optical components are exchanged according to the environmental differences (elevation difference, air pressure difference) between the assembly location and the installation location. Thereby, it is possible to correct (reduce) the change in the optical performance of the projection optical system 8 caused by the environmental difference. That is, it is possible to reduce the influence of the environmental difference between the assembly location and the installation location on the stroke of the lens 8a that can be driven by the drive mechanism 8b of the projection optical system 8 in the device manufacturing process. Therefore, regardless of the installation location of the exposure apparatus EXP, the device manufacturing recipe established at the assembly location can be commonly used at both the assembly location and the installation location.

[0045] When correcting the change in the optical performance of the projection optical system 8 due to the environmental difference between the assembly location and the installation location by the drive mechanism 8b of the projection optical system 8, a decrease in the resolution of the projection optical system 8 may occur along with the redevelopment or stroke expansion of the drive mechanism 8b. Therefore, it is difficult to expand the correction range of the change in the optical performance at an early stage. However, according to the above method of exchanging optical components, it is possible to correct the change in the optical performance of the projection optical system 8 due to the environmental difference with the thickness of the planar glass constituting the optical component attached (externally attached) to the projection optical system 8. Therefore, compared with coping with the stroke of the lens 8a by the drive mechanism 8b, the correction range can be expanded with a simple configuration. Therefore, the elevation limit (environmental difference correction limit) of the installation location of the exposure apparatus EXP becomes wide, and the installable area of the exposure apparatus EXP can be expanded.

[0046] According to the above method of exchanging optical components, it is also possible to enjoy the effect of reducing the influence of the environmental difference (air pressure difference) on the manufacturing equipment and processes of the exposure apparatus EXP. When the environmental difference between the assembly location and the installation location is large, it exceeds the inspection range of the manufacturing equipment as well as exceeding the air pressure correction limit of the exposure apparatus EXP. Therefore, although it is difficult to inspect the optical performance of the projection optical system 8 with the configuration of the exposure apparatus EXP at the installation location, it can be easily coped with by exchanging the optical components at the time of assembly and installation of the exposure apparatus EXP as in the above method.

[0047] The above method of replacing the optical component can also be effective for the projection optical system 8 alone. Since the manufacturing period of the projection optical system 8 is long, if a defect occurs in the projection optical system 8 mounted on the exposure apparatus EXP, there is a risk that the exposure apparatus EXP will be unusable for a long time until the replacement projection optical system 8 is completed. The projection optical system 8 is expensive, and since the environment for storing the projection optical system 8 also requires a high degree of stability, it was not realistic from a cost perspective to stock replacement projection optical systems for each elevation of the installation site. However, according to the above method, it is only necessary to stock one replacement projection optical system 8, and it becomes possible to respond by replacing the optical component according to the defect that occurred at the installation site of the exposure apparatus EXP.

[0048] Also, when exposure apparatuses EXP are respectively arranged at a plurality of locations where the environmental differences (elevation differences) are significantly different, a countermeasure method is assumed in which the projection optical system 8 of the exposure apparatus EXP with low usage frequency is replaced with the exposure apparatus EXP in which a defect has occurred. Such replacement work of the projection optical system 8 is large-scale and complicated in terms of transporting the heavy projection optical system 8 and mounting it on the exposure apparatus EXP, and can also be disadvantageous in terms of the cost required for the replacement work. According to the above method, by simply replacing the optical component attached to the projection optical system 8 of the exposure apparatus EXP, it is possible to quickly recover (cope with) the defect that has occurred in the optical performance of the projection optical system 8.

[0049] <Second Embodiment> The second embodiment according to the present invention will be described. The difference between this embodiment and the first embodiment is that not only the change in the optical performance of the projection optical system 8 due to the elevation difference (atmospheric pressure difference) but also the change in the optical performance of the projection optical system 8 that occurred during the assembly, transportation, or mounting of the projection optical system 8 on the exposure apparatus EXP is corrected with high precision. That is, in this embodiment, as the manufacturing parameter of the second optical component UnitB, in addition to the thickness of the planar glass, a parameter for adjusting the posture of the planar glass is given. Note that this embodiment basically inherits the first embodiment and can follow the first embodiment except for the matters mentioned below.

[0050] If only the optical components are exchanged according to the environmental differences (elevation difference, air pressure difference) between the assembly location and the installation location, the optical performance of the projection optical system 8 at the installation location may not meet the desired specifications. Specifically, even if the optical components are exchanged from the first optical component Unit A to the second optical component Unit B, at the installation location, the optical performance of the projection optical system 8 in the reference state where the lens 8a is arranged at the designed position of the lens in the stroke jet may not meet the desired specifications. In this case, when attaching the second optical component Unit B to the projection optical system 8, such as tilting and attaching the second optical component Unit B (the second light transmissive member) to the projection optical system 8, adjustment of the exposure apparatus EXP is required. And if the adjustment amount of the exposure apparatus EXP for making the optical performance of the projection optical system 8 meet the desired specifications at the installation location is determined at the assembly location, the adjustment of the exposure apparatus EXP at the installation location can be facilitated.

[0051] Hereinafter, a method for determining the adjustment amount of the exposure apparatus EXP when the exposure apparatus EXP is transferred from the assembly location (the first environment) to the installation location (the second environment) will be described. FIG. 9 is a flowchart showing the method for determining the adjustment amount of the exposure apparatus EXP. The flowchart of FIG. 9 can be performed at the assembly location. The flowchart of FIG. 9 may be performed by the control unit CU of the exposure apparatus EXP, or may be performed by an information processing apparatus (computer) provided outside the exposure apparatus EXP.

[0052] Hereinafter, an example of determining the tilt amount of the second optical component UnitB (second light transmissive member) with respect to the projection optical system 8 as the adjustment amount of the exposure apparatus EXP will be described. The tilt amount of the second optical component UnitB (second light transmissive member) with respect to the projection optical system 8 may include the amount of tilting (rotation) of the second optical component UnitB (second light transmissive member) with respect to the projection optical system 8 in at least one of the ωx direction, ωy direction, and ωz direction. The tilt amount may be expressed, for example, as the tilt angle with respect to each of the X, Y, and Z axes. The adjustment (change) of the tilt of the second optical component UnitB with respect to the projection optical system 8 may include changing at least one of the relative tilt of the planar glass 24 and 25 in the second optical component UnitB and the tilt of the planar glass 24 and 25 integrated with respect to the optical axis of the projection optical system 8. As described above, the change in the relative tilt (relative angle) of the planar glass 24 and 25 can be performed by relatively rotating the first holding portion 20 and the second holding portion 21. The change in the tilt of the planar glass 24 and 25 integrated with respect to the optical axis of the projection optical system 8 can be adjusted by rotating the fourth holding portion 31 with respect to the fifth holding portion 32 attached to the projection optical system 8.

[0053] In step S11, for the projection optical system 8 in the reference state to which the first optical component UnitA is attached, the optical performance in the environment of the assembly location (first environment) is measured. The measurement of the optical performance of the projection optical system 8 includes the measurement of the aberration of the projection optical system 8. The measurement of the aberration of the projection optical system 8 can be performed, for example, by the wavefront measurement unit 15 provided below the reference substrate 14. Also, as described above, the reference state is a state in which the lens 8a is arranged at the lens design position (reference position) within the stroke jet, and the stroke budget is the stroke range in which the lens 8a can be driven by the drive mechanism 8b. The lens design position (reference position) can be, for example, the position of the lens 8a where the upper stroke and the lower stroke of the lens 8a are the same.

[0054] In step S12, for the projection optical system 8 in the reference state with the second optical component UnitB attached, the optical performance in the environment (second environment) of the installation location is estimated (calculated). This estimation can be performed, for example, based on the measurement results of step S11, the air pressure difference (elevation difference) between the environment at the assembly location and the environment at the installation location, and the difference in thickness between the planar glasses 22 and 23 of the first optical component UnitA and the planar glasses 24 and 25 of the second optical component UnitB. Specifically, the correspondence between each of the air pressure (elevation) and the thickness of the planar glass of the optical component and the optical performance of the projection optical system 8 in the reference state is obtained in advance by a calculation formula or the like. Then, based on this correspondence, the change in the optical performance of the projection optical system 8 corresponding to the air pressure difference (elevation difference) between the environment at the assembly location and the environment at the installation location and the difference in thickness between the planar glass of the first optical component UnitA and the planar glass of the second optical component UnitB is calculated. Thereby, based on the calculated change in optical performance and the measurement results of step S11, the optical performance of the projection optical system 8 in the reference state with the second optical component UnitB attached in the environment (second environment) of the installation location can be estimated.

[0055] In step S13, the tilt amount when attaching the second optical component UnitB to the projection optical system 8 in the environment (second environment) of the installation location is determined so that the difference between the optical performance measured in step S11 and the optical performance estimated in step S12 is reduced. As described above, the tilt amount is the amount by which the second optical component UnitB (second light transmission member) is tilted with respect to the projection optical system 8 when attaching the second optical component UnitB to the projection optical system 8. The tilt amount may be understood as the adjustment amount of the exposure apparatus EXP when attaching the second optical component UnitB to the projection optical system 8 at the installation location. Further, when the adjustment amount (tilt amount) of the exposure apparatus EXP determined by the determination method shown in the flowchart of FIG. 9 is obtained, the exposure apparatus EXP is adjusted based on that adjustment amount in the environment (second environment) of the installation location.

[0056] As described above, in this embodiment, the adjustment amount of the exposure apparatus EXP for making the optical performance of the projection optical system 8 to which the second optical component UnitB is attached at the installation site meet the desired specifications is determined at the assembly site. Thereby, based on the adjustment amount of the exposure apparatus EXP determined at the assembly site, the exposure apparatus can be adjusted at the installation site. That is, the adjustment of the exposure apparatus EXP at the installation site can be facilitated.

[0057] Hereinafter, the adjustment of the exposure apparatus EXP (projection optical system 8) in this embodiment will be described. FIG. 10 is a diagram for explaining the adjustment of the exposure apparatus EXP in this embodiment.

[0058] First, the first optical component UnitA is attached to the projection optical system 8. Then, the projection optical system 8 to which the first optical component UnitA is attached is mounted on an inspection apparatus, and the optical performance of the projection optical system 8 is evaluated. The inspection apparatus records and stores the evaluation data 1 of the optical performance of the projection optical system 8 to which the first optical component UnitA is attached. The evaluation data 1 includes data obtained by separating the optical performance of the first optical component UnitA from the optical performance of the projection optical system 8.

[0059] Next, the projection optical system 8 to which the first optical component UnitA is attached is mounted on the exposure apparatus EXP. Then, an inspection of the optical performance of the exposure apparatus EXP is carried out, and the evaluation data 2 of the optical performance of the exposure apparatus EXP is recorded and stored. Based on the evaluation data 1 and the evaluation data 2, for the second optical component UnitB to be attached to the projection optical system 8, the attitude variation of the optical elements (plane glasses 24, 25) during the period from the assembly of the projection optical system 8 to its mounting on the exposure apparatus EXP is calculated. Then, the correction amount of the attitudes of the plane glasses 24, 25 when the lens 8a is arranged at the lens design position (reference position) by the drive mechanism 8b is calculated.

[0060] In the second optical component UnitB, based on the correction value calculated as described above, the attitude variation of the optical element is corrected during the manufacture of the exposure apparatus EXP. Also, in the second optical component UnitB, the attitudes of the planar glasses 24 and 25 are adjusted using the change mechanism etc. of the second optical component UnitB so that the optical performance of the projection optical system 8 at the installation site satisfies the specifications. The second optical component UnitB is configured as an inventory unit of the exposure apparatus EXP. The second optical component UnitB is exchanged with the first optical component UnitA when installing the exposure apparatus EXP at the installation site.

[0061] FIG. 11 is a diagram for explaining the stroke budget in the projection optical system 8 of the present embodiment. The second optical component UnitB in the present embodiment is adjusted to a state where the attitudes of the planar glasses 24 and 25 are corrected based on evaluation data 1 to 2 etc. Therefore, when mounting the second optical component UnitB on the exposure apparatus EXP (that is, when attaching it to the projection optical system 8), the position of the lens 8a inside the projection optical system 8 can be arranged at the lens design position (reference position) by the drive mechanism 8b. As a result, it is possible to return, that is, reduce, the bias between the upper stroke and the lower stroke of the lens 8a that occurred from the lens adjustment process to the mounting of the exposure apparatus. Note that the lens design position (reference position) may be understood as the initial position before lens position adjustment.

[0062] According to the present embodiment, in addition to the effects of the first embodiment described above, there is an effect of improving the error handling ability of the exposure apparatus EXP in case an unknown error occurs in the device manufacturing process at the installation site (for example, high altitude).

[0063] <Third Embodiment> The third embodiment according to the present invention will be described. In this embodiment, a modified example of the optical component attached to the projection optical system 8 will be described. Note that this embodiment basically inherits the first embodiment and may follow the first embodiment except for the matters mentioned below. Also, this embodiment may further apply the second embodiment.

[0064] Hereinafter, a configuration example of the second optical component UnitB in the present embodiment will be described. Note that the first optical component UnitA may have the same configuration as the second optical component UnitB. FIG. 12 is a schematic diagram showing a configuration example of the first holding portion 40 of the second optical component UnitB in the present embodiment. FIG. 13 is a schematic diagram of the first holding member 42 and its periphery in the first holding portion 40 of the present embodiment as viewed from above (+Z direction). FIG. 14 is a diagram for explaining the behavior of the leaf spring 44 and the adjustment screw 46 in the first holding portion 40 of the present embodiment.

[0065] The planar glass 41 is fixed to the first holding member 42. Specifically, the planar glass 41 is mounted on the protrusion 42a (protrusion surface) of the first holding member 42. The protrusions 42a are arranged, for example, at three positions on the circumference outside the exposure light beam diameter at a 120° pitch. The annular leaf spring retainer 43 has protrusions at three positions facing the protrusions 42a of the first holding member 42 via the planar glass 41. The planar glass 41 is fixed to the first holding member 42 by being sandwiched between the protrusion 42a of the first holding member 42 and the leaf spring retainer 43. As the material of the first holding member 42, a material capable of elastic deformation is used. For example, nickel alloys such as carbon steel, stainless steel, and invar, aluminum alloys, copper alloys such as brass, and ceramic materials are suitable.

[0066] The leaf spring 44 is an annular elastic body. The leaf spring 44 is fixed to the first holding member 42 by the leaf spring retainer 45 at three positions on the circumference at a 120° pitch. As the material of the leaf spring 44, spring materials such as stainless steel sheets for springs and phosphor bronze sheets for springs are suitable.

[0067] The adjustment screw 46 is a mechanism for adjusting the posture of the planar glass 41 as an optical element. The adjustment screw 46 is disposed in the tap of the first holding member 42, and is circumferentially disposed below the leaf spring 44 at the same angular phase as the protrusion 42a. By rotating the adjustment screw 46, the leaf spring 44 can be displaced vertically. When the leaf spring 44 is displaced upward, an upward spring force acts on the leaf spring 44. At this time, a downward spring force is generated in the first holding member 42. The upward spring force and the downward spring force are equal, and the movement amount of the adjustment screw 46 is the sum of the displacement of the leaf spring 44 and the displacement of the first holding member 42.

[0068] Since both ends of the leaf spring 44 are fixed by the leaf spring retainer 45, the leaf spring 44 bends between the leaf spring retainers 45 and generates a downward reaction force. Due to this reaction force, the protrusion 42a of the first holding member 42 is displaced downward. A structure in which both sides of the protrusion 42a are notched is preferable so that the protrusion 42a of the first holding member 42 is easily displaced. Since the three protrusions 42a are individually displaced, the posture of the planar glass 41 can be adjusted. Since the adjustment screw 46 receives a spring force downward by the leaf spring 44, the adjustment screw 46 is structured not to move due to stage vibration or the like.

[0069] The first holding member 42 is fastened to the second holding member 47. The second holding member 47 and the third holding member 49 are connected by a connecting member 48. By loosening the fixing bolt 49a with respect to the third holding member 49, the inside of the connecting member 48 can be integrally rotated with respect to the optical axis of the projection optical system 8. The first holding part 40 is detachable from the projection optical system 8 on the upper surface of the third holding member 49, and is structured to be replaceable with the optical component in the device inventory without removing the projection optical system 8 from the main body of the exposure apparatus EXP.

[0070] As described in the second embodiment, the surface of the planar glass 41 can be stocked in the exposure apparatus EXP in a state of being aspherically processed based on the evaluation data 1 to 2. Further, in the third embodiment, with respect to the first to second embodiments, it is possible to perform attitude correction of the optical element (planar glass) according to the environmental differences (elevation difference, air pressure difference) between the assembly location and the installation location.

[0071] <Fourth Embodiment> The fourth embodiment according to the present invention will be described. This embodiment is characterized in that, for each stocked optical component, optimization of the position of the optical component in the exposure apparatus EXP is performed. In the fourth embodiment, at least one of the adjustment spacer 12SP of the surface position detection unit 12 and the adjustment spacer 13SP of the alignment scope 13 is replaceable according to the adjustment of the first optical component UnitA and the second optical component UnitB. Note that this embodiment basically inherits the first embodiment and may follow the first embodiment except for the matters mentioned below. Further, this embodiment may further apply at least one of the second to third embodiments.

[0072] Hereinafter, the adjustment of the exposure apparatus EXP (projection optical system 8) in this embodiment will be described. First, as described in the second embodiment, the evaluation data 1 to 2 are acquired. For the second optical component UnitB, an optimization calculation having the following three parameters as calculation items is performed. The first parameter is the optical performance of the suitable projection optical system 8 at the installation location. The second parameter is the correction of the attitude variation of the optical element (planar glass) from the assembly of the projection optical system 8 to its mounting on the exposure apparatus EXP. The third parameter is the image plane position of the suitable projection optical system 8 at the installation location. According to the optimization calculation result, the attitude of the optical element (planar glass) is corrected using the change mechanism etc. of the second optical component UnitB, and the attitudes of the planar glasses 24 and 25 are adjusted so that the optical performance of the projection optical system 8 satisfies the specifications at the installation location.

[0073] Furthermore, in the present embodiment, the appropriate thicknesses of the adjustment spacers 12SP and 13SP are calculated so that the image plane positions of the surface position detection unit 12 and the alignment scope 13 coincide with the image plane position of the projection optical system 8 at the installation site. The adjustment spacers 12SP and 13SP are stored (memorized) in the exposure apparatus EXP in association with the optical components attached to the projection optical system 8. For example, the adjustment spacers 12SP and 13SP used when attaching the first optical component UnitA to the projection optical system 8 are stored (memorized) in the exposure apparatus EXP in association with the first optical component UnitA. Also, the adjustment spacers 12SP and 13SP used when attaching the second optical component UnitB to the projection optical system 8 are stored (memorized) in the exposure apparatus EXP in association with the second optical component UnitB.

[0074] Here, in the present embodiment, an adjustment term for the reticle surface position (object surface) may be added to the calculation terms used for the optimal calculation during the manufacture of the second optical component UnitB. The adjustment of the reticle surface position can be performed by replacing the adjustment spacer 7SP described in FIG. 1.

[0075] <Fifth Embodiment> The fifth embodiment according to the present invention will be described. In the present embodiment, a modified example of the optical component attached to the projection optical system 8 will be described. Note that the present embodiment basically inherits the first embodiment and may follow the first embodiment except for the matters mentioned below. Also, the present embodiment may further apply at least one of the second to fourth embodiments.

[0076] Hereinafter, a configuration example of the second optical component UnitB in the present embodiment will be described, but the first optical component UnitA may have the same configuration as the second optical component UnitB. FIG. 15 is a schematic diagram showing a configuration example of the first holding unit 50 of the second optical component UnitB in the present embodiment. FIG. 16 is a schematic diagram showing a configuration example of the change mechanism in the first holding unit 50 of the present embodiment. FIG. 17 is a schematic diagram showing a cross section of the first holding unit 50 of the present embodiment. FIG. 18 is a diagram for explaining the behavior of the change mechanism in the first holding unit 50 of the present embodiment.

[0077] The planar glass 51 is fixed to the first holding member 52. Since the holding structure of the planar glass 51 by the first holding member 52 is the same as that described in the first embodiment or the third embodiment, the description here is omitted. The first holding member 52 is made of a material having a coefficient of linear expansion substantially equal to that of the planar glass 51. For example, when the planar glass 51 is quartz, a super-invar material can be used as the material of the first holding member 52. With such a configuration, when the environmental temperature fluctuates, the generation of external force caused by the relative thermal fluctuation between the first holding member 52 and the planar glass 51 due to the difference in linear thermal expansion can be reduced.

[0078] The elastic members 53 are arranged at three locations on the outer peripheral portion of the first holding member 52 at a 120° pitch, and apply an elastic force to the first holding member 52. The elastic member 53 is composed of, for example, a first leaf spring 54 and a second leaf spring 55 as shown in FIG. 16. The first leaf spring 54 is bendable (elastic coefficient k1) in the radial direction of the planar glass 51, and is connected to the first holding member 52 and the second leaf spring 55. The first leaf spring 54 generates a first elastic force F1 from the second elastic force F2 applied from the second leaf spring 55, and applies the first elastic force F1 to the first holding member 52. As shown in FIG. 16, the first leaf spring 54 and the second leaf spring 55 may have an integral structure.

[0079] The second leaf spring 55 is bendable (elastic coefficient k2) in the radial direction of the planar glass 51, and is connected to the first leaf spring 54 and a biasing portion 56 described later. The second leaf spring 55 generates a second elastic force F2 from the pressing force F applied from the biasing portion 56, and applies the second elastic force F2 to the first leaf spring 54.

[0080] The elastic member 53 has a spherical portion 57 from the viewpoint of position reproducibility when contacting the biasing portion 56. As shown in FIGS. 16 to 17, the spherical portion 57 is arranged at the central portion of the elastic member 53 in the radial direction (horizontal direction), and is arranged at a position eccentric from the central portion of the elastic member 53 in the optical axis direction (vertical direction) of the projection optical system 8.

[0081] The biasing portion 56 is connected to the elastic member 53 and applies a pressing force to the elastic member 53. One suitable means for the biasing portion 56 is a micrometer. The biasing portion 56 constituted by the micrometer is supported by the second holding member 58 and can adjust the pushing-in amount with a resolution of, for example, 10 μm or less. Note that the biasing portion 56 may have a screw structure.

[0082] Next, with reference to FIG. 18, the operation of the adjustment mechanism in the first holding portion 50 of the present embodiment will be described. A pressing force F is applied to the second leaf spring 55 by the biasing portion 56 supported by the second holding member 58. The second leaf spring 55 to which the pressing force F is applied deforms in the radial direction of the flat glass 51. On the other hand, in the optical axis direction of the projection optical system 8, since the application point (spherical portion 57) of the biasing portion 56 is eccentric, the pressing force F is also applied eccentrically, and the second leaf spring 55 behaves so as to rotate around the tangential axis.

[0083] Therefore, the second elastic force F2 generated from the second leaf spring 55 is also applied eccentrically to the first leaf spring 54. The first leaf spring 54 to which the second elastic force F2 is applied deforms in the radial direction of the flat glass 51. However, similar to the second leaf spring 55, since the second elastic force F2 is applied eccentrically, it twists so as to rotate around the tangential axis. Therefore, the first elastic force F1 generated from the first leaf spring 54 is applied to the first holding member 52 from an oblique direction, and the flat glass 51 fixed to the first holding member 52 is tilted. By synthesizing the pushing-in amounts of the biasing portions 56 by the adjustment mechanisms arranged at three positions at equal intervals with a 120° pitch, it is possible to adjust the flat glass 51 to have a desired tilt angle in an arbitrary direction.

[0084] As described above, the optical component of this embodiment can adjust the orientation of the planar glass 51 with high precision from outside the projection optical system 8. Therefore, after the second optical component UnitB is attached to the projection optical system 8, the wavefront measurement unit 15 measures the aberration of the projection optical system 8. The control unit CU determines whether the aberration measurement data transmitted from the wavefront measurement unit 15 is within the allowable range. If the aberration is outside the allowable range, the control unit CU calculates the tilt angle of the second optical unit UnitB so that the aberration is within the allowable range. Based on this calculation result, the pushing amount of the biasing unit 56 can be adjusted, and the optical performance of the projection optical system 8 can be adjusted within the allowable range. Note that the wavefront measurement unit 15 may not be used, and the substrate may be exposed and the aberration may be measured from the exposure result.

[0085] <Sixth Embodiment> The sixth embodiment according to the present invention will be described. This embodiment basically inherits the fifth embodiment and can follow the fifth embodiment except for the matters mentioned below.

[0086] FIG. 19 is a schematic diagram showing a configuration example of the first holding unit 50 of the second optical component UnitB in this embodiment. The first holding unit 50 of this embodiment is provided with a drive actuator 59a in the biasing unit 56 and a detection unit 59b for detecting the pushing amount of the biasing unit 56, as compared with the fifth embodiment. Suitable forms of the drive actuator 59a include a pulse motor and a piezo element. Suitable forms of the detection unit 59b include a rotary encoder for detecting the rotation angle of the pulse motor and a linear encoder for detecting the shaft position of the biasing unit 56.

[0087] In addition, the second optical component UnitB of this embodiment is provided with a component control unit CUa for controlling the orientation of the planar glass 51. The control unit CUa has a parameter file for controlling the orientation of the planar glass for each optical component. Note that the component control unit CUa may be included in the control unit CU of the exposure apparatus EXP.

[0088] According to this embodiment, at the time of manufacturing the second optical component UnitB, a parameter file is created for correcting the posture of the optical element (plane glass) and controlling the posture of the optical element so that the optical performance of the projection optical system 8 meets the specifications at the installation point. The parameter file is stored in the control unit CU of the exposure apparatus EXP. When replacing with the second optical component UnitB stocked in the exposure apparatus EXP, the parameter file used by the component control unit CUa is replaced with the parameter file for the second optical component UnitB, and the posture of the optical element (plane glass) of the second optical component UnitB is controlled. Next, the aberration measurement of the projection optical system 8 is performed by the wavefront measurement unit 15. The control unit CU determines whether the result of the aberration measurement is within the allowable range, and if the aberration is outside the allowable range, calculates the tilt angle of the second optical component UnitB so that the aberration is within the allowable range. The component control unit CUa controls the adjustment mechanism of the second optical component UnitB so as to have the tilt angle calculated by the control unit CU, and adjusts the tilt of the second optical component UnitB (that is, the tilt of the plane glass).

[0089] Next, a modified example of the second optical component UnitB in this embodiment will be described. FIG. 20 is a schematic view showing a modified example of the first holding portion 60 of the second optical component UnitB in this embodiment. FIG. 20(a) is a top view of the first holding portion 60 viewed from above (+Z direction). The first holding portion 60 may include a plane glass 61, a first holding member 62, a plurality (four locations) of holding portions 63a to 63d that are fixed to the first holding member 62 and hold the outer peripheral portion of the plane glass 61, and a biasing portion 64 that biases the first holding member 62. FIG. 20(b) shows a configuration example of the holding portion 63a, FIG. 20(c) shows configuration examples of the holding portions 63c to 63d, and FIG. 20(d) shows a configuration example of the holding portion 63b.

[0090] The first holding member 62 is composed of a first support member 62a and a second support member 62b located below it. The first support member 62a and the second support member 62b are fixed via four holding portions 63a to 63d that are evenly arranged with respect to the central position of the annular shape.

[0091] In the holding part 63a, as shown in FIG. 20(b), the end of the first clamping part 65 contacts the inner surface of the first support member 62a, and the first clamping part 65 is fixed to the first support member 62a. The first clamping part 65 that contacts the upper surface of the flange part 61a (notch surface) formed on the outer peripheral part of the flat glass 61 and the second clamping part 66 that contacts the lower surface of the flange part 61a sandwich the flange part 61a with a load not exceeding the breaking strength of the flat glass 61. An elastic member 67 that generates a clamping force is disposed between the first clamping part 65 and the second clamping part 66. A hinge member 68 is disposed between the first support member 62a and the second support member 62b in the holding part 63a. The hinge member 68 can be configured to slightly rotate the first support member 62a and the second support member 62b.

[0092] In each of the holding parts 63c to 63d, as shown in FIG. 20(c), the end of the second clamping part 66 contacts the inner surface of the second support member 62b, and the second clamping part 66 is fixed to the second support member 62b. Other parts of the holding structure of the flat glass 61 in each of the holding parts 63c to 63d are the same as those of the holding part 63a, but the hinge member 68 is not configured in each of the holding parts 63c to 63d.

[0093] In the holding part 63b, as shown in FIG. 20(d), the end of the first clamping part 65 contacts the inner surface of the first support member 62a, and the first clamping part 65 is fixed to the first support member 62a. A biasing part 64 is disposed between the first support member 62a and the second support member 62b. The biasing part 64 can include a hinge mechanism 69 as a changing mechanism that changes the displacement direction in order to relatively displace the first support member 62a and the second support member 62b, and a drive actuator 70 that biases the hinge mechanism 69. The displacement output of the drive actuator 70 is displacement-converted in the optical axis direction of the projection optical system 8 by the hinge mechanism 69.

[0094] Further, a gap sensor (not shown) may be disposed between the first support member 62a and the second support member 62b. The gap sensor sequentially measures the relative displacement amount between the first support member 62a and the second support member 62b. Thereby, the control unit CU (or the component control unit CUa) can control the drive actuator 70 based on the measurement result of the gap sensor.

[0095] When a force is applied from the drive actuator 70 to the hinge mechanism 69, the first support member 62a and the second support member 62b are displaced relative to each other in the vertical direction along the optical axis direction of the projection optical system 8. Next, the hinge member 68 slightly rotates the first support member 62a and the second support member 62b about the vicinity of the center of the hinge member 68 as the rotation center. The holding portions 63a to 63b are fixed to the first support member 62a side, and the holding portions 63c to 63d are fixed to the second support member 62b side. Since only the first support member 62a is fixed to the projection optical system 8 which is a high-rigidity structure, the peripheral portions of the planar glass 61 held by the holding portions 63c to 63d both receive a load downward in the optical axis direction of the projection optical system 8. This load is transmitted inside the planar glass 61, and the peripheral portions of the planar glass 61 held by the holding portions 63a to 63b both receive a load upward in the optical axis direction of the projection optical system 8. Thereby, due to the displacement output of the drive actuator 70, a shape change may occur in the planar glass 61 such that it bulges from the holding portion 63a toward the holding portion 63b and is concave from the holding portion 63c toward the holding portion 63d.

[0096] When attaching the first optical component UnitA or the second optical component UnitB to the projection optical system 8, correlation data between the output value of the gap sensor during the driving of the drive actuator 70 and the amount of shape change of the flat glass 61 obtained by the wavefront measurement unit 15 is acquired. The correlation data is stored in the parameter file for each optical component of the exposure apparatus EXP. Then, the difference in the amount of deformation due to the difference in the thickness of the flat glass between the first optical component UnitA and the second optical component UnitB can be handled by the parameter file configured for each optical component. Thereby, the control unit CU of the exposure apparatus EXP can quickly drive the amount of aberration of the entire projection optical system 8 to a desired amount based on the parameter file.

[0097] <Seventh Embodiment> The seventh embodiment according to the present invention will be described. This embodiment basically inherits the sixth embodiment and can follow the sixth embodiment except for the matters mentioned below. This embodiment is characterized in that it has individual parameter files for the entire projection optical system 8 for each optical component.

[0098] In this embodiment, each optical component has a parameter file for the position and orientation of the lens 8a that can be moved by one or more drive mechanisms 8b provided in the projection optical system 8. As the types of the drive mechanisms 8b, there are a drive mechanism for linearly driving the lens in the optical axis direction (Z direction) of the projection optical system 8 and a drive mechanism for rotationally driving the lens in ωx and ωy. Also, as the types of the drive mechanisms 8b, there are a drive mechanism for linearly driving the lens in a direction (XY direction) perpendicular to the optical axis direction of the projection optical system 8 and a drive mechanism for rotationally driving the lens in ωz. Note that the combination of the directions for driving the lens by the drive mechanism is not limited to the above, and it is possible to combine a plurality of azimuth axes. For example, it is also possible to configure a drive mechanism that can drive a maximum of six-axis azimuth using a parallel link mechanism with one drive mechanism.

[0099] <Eighth Embodiment> An eighth embodiment according to the present invention will be described. This embodiment basically inherits the first embodiment and may follow the first embodiment except for the matters mentioned below. Further, this embodiment may further apply at least one of the second to seventh embodiments.

[0100] This embodiment is characterized in that the adjustment of the second optical component UnitB and the adjustment of the exposure apparatus EXP are performed using the exposure apparatus EXP and the facilities of the device manufacturing factory. For example, the flow when the exposure apparatus EXP is transferred from the first environment (for example, a location with a low altitude) to the second environment (for example, a location with a high altitude) is described below.

[0101] First, in the exposure apparatus EXP before transfer, the exposure apparatus EXP is set to a state in which the optical characteristics of the projection optical system 8 after transfer can be calculated. For example, one or more lenses 8a in the projection optical system 8 are driven by a drive mechanism 8b and moved to a position where the optical characteristics after transfer can be estimated. The position where the optical characteristics after transfer can be estimated may be the lens design position (reference position). Note that it is only necessary to be able to calculate the optical characteristics of the projection optical system 8 after transfer, and the products manufactured using the exposure apparatus EXP do not have to satisfy the specifications.

[0102] Next, the optical performance of the projection optical system 8 after transfer is calculated, and the adjustment amount of the second optical component UnitB attached to the projection optical system 8 and the displacement amount of the image plane position are estimated (calculated) so that the optical performance of the projection optical system 8 satisfies a predetermined specification. The estimation is performed using the wavefront measurement unit 15 of the exposure apparatus EXP and an application for predicting the exposure result built in the exposure apparatus EXP. Alternatively, the estimation may be performed using a device provided outside the exposure apparatus EXP (a device for measuring the optical performance of the projection optical system 8). Further, based on the estimation result, the thickness of the adjustment spacer 12SP for adjusting the focal position (image plane position) of the surface position detection unit 12 and the thickness of the adjustment spacer 13SP for adjusting the focal position (image plane position) of the alignment scope 13 are determined. Thereby, the adjustment spacers 12SP and 13SP having the determined thicknesses can be prepared before the exposure apparatus EXP is transferred.

[0103] When relocating the exposure apparatus EXP, the optical components attached to the projection optical system 8 are replaced from the first optical component UnitA to the second optical component UnitB. Also, the prepared adjustment spacer 12SP is disposed between the surface position detection unit 12 and its support member, and the prepared adjustment spacer 13SP is disposed between the alignment scope 13 and its support member.

[0104] In the exposure apparatus EXP after relocation, the optical performance of the projection optical system 8 is measured in the same manner as before relocation. Based on this measurement result, the adjustment mechanism attached to the second optical component UnitB is finely adjusted manually or automatically by the control unit CU of the exposure apparatus EXP. Also, in the exposure apparatus EXP after relocation, using the TTL (Through The Lens) type focus measurement system provided in the apparatus, the amount of focus position deviation between the object plane (reticle plane) and the image plane (wafer plane) can be measured. If the measured amount of focus position deviation is less than a predetermined threshold value, the parallel plane glass inside the optical system of the surface position detection unit 12 is tilted to correct the image plane position of the surface position detection unit 12. Also, if the measured amount of focus position deviation is less than a predetermined threshold value, the lens position of the focus drive mechanism in the optical system of the alignment scope 13 is offset to correct the image plane position. Note that the configuration of the parallel plane glass and the configuration of the focus drive mechanism can be appropriately selected. On the other hand, if the measured amount of focus position deviation is equal to or greater than a predetermined threshold value, the prepared adjustment spacers 12SP, 13SP are applied.

[0105] <Embodiment of a method for manufacturing an article> The article manufacturing method according to an embodiment of the present invention is suitable for manufacturing articles such as microdevices such as semiconductor devices and elements having fine structures. The article manufacturing method of the present embodiment includes an exposure step of exposing a substrate using an exposure apparatus adjusted by the above adjustment method (a step of forming a pattern on the substrate), a processing step of processing the substrate exposed in the exposure step, and a manufacturing step of manufacturing an article from the substrate processed in the processing step. The processing step may include a step of developing the substrate exposed in the exposure step. Further, such an article manufacturing method includes other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.). The article manufacturing method of the present embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article as compared with the conventional method.

[0106] <Other Embodiments> The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiment to a system or apparatus via a network or a storage medium, and causing one or more processors in a computer of the system or apparatus to read and execute the program. Further, it can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

[0107] <Summary of Embodiments> The disclosure of this specification includes at least the following determination method, adjustment method, and article manufacturing method. (Item 1) A determination method for determining an adjustment amount of the exposure apparatus when transferring an exposure apparatus having a projection optical system from a first environment to a second environment, A measurement step of measuring the optical performance of the projection optical system in the reference state in which the first optical component having the first light transmission member is attached in the first environment, An estimation step of estimating the optical performance of the projection optical system in the second environment for the reference state in which the second optical component having the second light transmission member having a different thickness from the first light transmission member is attached, A determination step of determining an inclination amount of the second light transmissive member when attaching the second optical component to the projection optical system in the second environment so that a difference between the optical performance measured in the measurement step and the optical performance estimated in the estimation step is reduced; comprising The projection optical system includes a lens and a drive mechanism that drives the lens. The reference state is a state in which the lens is disposed at a reference position within a stroke range in which the lens can be driven by the drive mechanism. The determination method is characterized by this. (Item 2) In the estimation step, based on the measurement result of the measurement step, the atmospheric pressure difference between the first environment and the second environment, and the difference in thickness between the first light transmissive member and the second light transmissive member, the optical performance of the projection optical system in the reference state with the second optical component attached thereto in the second environment is estimated. The determination method according to item 1, characterized by this. (Item 3) The inclination amount includes an amount of inclination of the second light transmissive member with respect to the projection optical system about an axis in at least one of a first direction along the optical axis of the projection optical system and a second direction perpendicular to the first direction. The determination method according to item 1 or 2, characterized by this. (Item 4) The second environment has a different atmospheric pressure from the first environment. The determination method according to any one of items 1 to 3, characterized by this. (Item 5) The second environment has a different altitude from the first environment. The determination method according to any one of items 1 to 4, characterized by this. (Item 6) The first optical component includes a plurality of the first light transmissive members and a first change mechanism for changing the inclination of each of the plurality of the first light transmissive members. The second optical component includes a plurality of the second light transmissive members and a second change mechanism for changing the inclination of each of the plurality of the second light transmissive members. The determination method according to any one of items 1 to 5, characterized by this. (Item 7) The determination method according to any one of Items 1 to 6, wherein each of the first light transmissive member and the second light transmissive member is a glass plate. (Item 8) An adjustment method for adjusting an exposure apparatus transferred from a first environment to a second environment, an acquisition step of acquiring an adjustment amount of the exposure apparatus determined by the determination method according to any one of Items 1 to 7; an adjustment step of adjusting the exposure apparatus in the second environment based on the adjustment amount acquired in the acquisition step; The adjustment method characterized by including these. (Item 9) an exposure step of exposing a substrate using the exposure apparatus adjusted by the adjustment method according to Item 8; a processing step of processing the substrate exposed in the exposure step; a manufacturing step of manufacturing an article from the substrate processed in the processing step; The article manufacturing method characterized by including these.

[0108] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Therefore, claims are attached to disclose the scope of the invention.

Explanation of Reference Numerals

[0109] EXP: Exposure apparatus, 3: Illumination optical system, 6: Master, 7: Master stage, 8: Projection optical system, 9: Substrate, 10: Chuck, 11: Substrate stage, 12: Surface position detection unit, 13: Alignment scope, 14: Reference substrate, 15: Wavefront measurement unit

Claims

1. A determination method for determining an adjustment amount of an exposure apparatus having a projection optical system when transferring the exposure apparatus from a first environment to a second environment, comprising: a measurement step of measuring the optical performance of the projection optical system in the reference state in which a first optical component having a first light transmissive member is attached in the first environment; an estimation step of estimating the optical performance of the projection optical system in the second environment with respect to the reference state in which a second optical component having a second light transmissive member with a different thickness from the first light transmissive member is attached; a determination step of determining an inclination amount of the second light transmissive member when attaching the second optical component to the projection optical system in the second environment so that the difference between the optical performance measured in the measurement step and the optical performance estimated in the estimation step is reduced; wherein the projection optical system includes a lens and a drive mechanism for driving the lens; the reference state is a state in which the lens is disposed at a reference position within a stroke range in which the lens can be driven by the drive mechanism, and the determination method is characterized by this.

2. In the estimation step, the optical performance of the projection optical system in the second environment with respect to the reference state in which the second optical component is attached is estimated based on the measurement result of the measurement step, the air pressure difference between the first environment and the second environment, and the difference in thickness between the first light transmissive member and the second light transmissive member. The determination method according to claim 1, characterized by this.

3. The inclination amount includes an amount of inclination of the second light transmissive member around an axis in at least one direction among a first direction along the optical axis of the projection optical system and a second direction perpendicular to the first direction with respect to the projection optical system. The determination method according to claim 1, characterized by this.

4. The second environment has a different air pressure from the first environment. The determination method according to claim 1, characterized by this.

5. The second environment has a different altitude from the first environment. The determination method according to claim 1, characterized by this.

6. The first optical component includes a plurality of the first light transmissive members and a first change mechanism for changing the inclination of each of the plurality of the first light transmissive members; The second optical component includes a plurality of the second light transmissive members and a second change mechanism for changing the inclination of each of the plurality of the second light transmissive members. The determination method according to claim 1, characterized by this.

7. The determination method according to claim 1, wherein each of the first light transmissive member and the second light transmissive member is a glass plate.

8. An adjustment method for adjusting an exposure apparatus transferred from a first environment to a second environment, an acquisition step of acquiring an adjustment amount of the exposure apparatus determined by the determination method according to any one of claims 1 to 7; an adjustment step of adjusting the exposure apparatus in the second environment based on the adjustment amount acquired in the acquisition step; The adjustment method characterized by including these.

9. an exposure step of exposing a substrate using the exposure apparatus adjusted by the adjustment method according to claim 8; a processing step of processing the substrate exposed in the exposure step; a manufacturing step of manufacturing an article from the substrate processed in the processing step; The article manufacturing method characterized by including these.

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