KR20220000809A - Method of manufacturing transmission type optical element, exposure apparatus, method of manufacturing article, and transmission type optical element - Google Patents

Abstract

The present invention relates to a method for manufacturing a light-transmitting optical element, including: a first process of forming an anti-reflective film on the surface of the optical element; and a second process of removing the anti-reflective film formed in the first process in the thickness direction of the anti-reflective film, wherein the anti-reflective film is removed in the thickness direction so that at least a part of the anti-reflective film can remain even in a region where the anti-reflective film is removed in the second process.

Description

A manufacturing method for manufacturing a transmissive optical element, an exposure apparatus, a manufacturing method for an article, and a transmissive optical element TECHNICAL FIELD

The present invention relates to a manufacturing method for manufacturing a transmissive optical element, an exposure apparatus, a manufacturing method for an article, and a transmissive optical element.

In a lithography process for manufacturing articles such as semiconductor devices, an exposure apparatus having an illumination optical system for illuminating an original plate and a projection optical system for projecting a pattern of the original plate illuminated by the illumination optical system onto a substrate is used. By projecting the pattern of the original plate onto the substrate, the pattern is transferred to the resist (photosensitive agent) arranged (applied) on the surface of the substrate. In the exposure apparatus, if the illumination of the original plate is non-uniform, there is a possibility that the pattern transfer to the resist on the substrate cannot be performed satisfactorily. Accordingly, in the illumination optical system, a rod-type optical integrator or an optical integrator including a plurality of two-dimensionally arranged wavefront dividing elements is used in order to illuminate the original plate with a uniform illuminance.

On the other hand, in the illumination optical system, non-uniformity may be recognized in the illuminance distribution on the illuminated surface due to contamination or eccentricity of the optical system, non-uniformity of the antireflection film, or the like. Therefore, by arranging a filter provided with a dot pattern (light-shielding material) on a quartz substrate at a position optically conjugated to the illuminated surface, and changing the density (transmittance distribution) of the dots, the illuminance distribution on the illuminated surface A technique for equalizing is disclosed in Japanese Patent Laid-Open No. 2006-210554.

However, in the technique disclosed in Japanese Patent Laid-Open No. 2006-210554, it is difficult to equalize the illuminance distribution on the surface to be illuminated with sufficient precision. For example, when it is necessary to slightly change the transmittance by means of a filter, since the number of dots decreases, the transmittance error due to an error in the size of the dots increases, and the illuminance distribution on the illuminated surface can be corrected with high precision. can't

The present invention provides a technique related to a transmissive optical element advantageous for uniform illuminance distribution on a surface to be illuminated.

In order to achieve the above object, a manufacturing method as one aspect of the present invention is a manufacturing method for manufacturing a light-transmitting optical element, comprising a first step of forming an anti-reflection film on the surface of the optical element, and in the first step a second step of removing the formed antireflection film in a thickness direction of the antireflection film, wherein in the second step, the antireflection film is formed so that at least a portion of the antireflection film remains even in a region where the antireflection film is removed. It is characterized in that it is removed in the thickness direction.

Another object or other aspect of the present invention will become apparent from the embodiments described below with reference to the accompanying drawings.

ADVANTAGE OF THE INVENTION According to this invention, the technique regarding the transmission type optical element which is advantageous for making the illuminance distribution in the to-be-illuminated surface uniform, for example can be provided.

1 is a schematic diagram showing the configuration of an exposure apparatus as an aspect of the present invention.
Fig. 2 is a schematic diagram showing the configuration of a light-transmitting optical element.
3 is a flowchart for explaining a manufacturing method for manufacturing an optical element according to an aspect of the present invention.
Fig. 4 is a flowchart for explaining the step S02 shown in Fig. 3 in detail.
5A to 5D are diagrams for explaining the step S02 shown in FIG. 3 in detail.
Fig. 6 is a view for explaining in detail the step S02 shown in Fig. 3;
Fig. 7 is a view for explaining a specific method of the removal processing in S24 shown in Fig. 4;
Fig. 8 is a view for explaining a specific method of the removal processing in S24 shown in Fig. 4;
9A to 9D are diagrams for explaining a specific method of the removal processing in S24 shown in FIG.
10A to 10C are diagrams for explaining a specific method of the removal processing in S24 shown in FIG.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. At this time, the following embodiment does not limit the invention concerning a claim. Although the plurality of features are described in the embodiment, it cannot be said that all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. In addition, in the accompanying drawings, the same reference numerals are attached to the same or similar components, and overlapping descriptions are omitted.

1 is a schematic diagram showing the configuration of an exposure apparatus 100 as an aspect of the present invention. The exposure apparatus 100 is, for example, a lithographic apparatus used in a manufacturing process (lithography process) of a semiconductor device etc., and forms a pattern on a board|substrate. The exposure apparatus 100 exposes the substrate W via the original plate R. In this embodiment, the substrate W is exposed (scanning exposure) while the original plate R and the substrate W are moved in the scanning direction, and the pattern of the original plate R is applied to the substrate. It is a step-and-scan exposure apparatus (scanner) that transfers. However, the exposure apparatus 100 may employ a step-and-repeat method or other exposure method.

As shown in FIG. 1 , the exposure apparatus 100 includes an illumination optical system 101 , a disk drive unit 102 , a projection optical system 103 , a substrate drive unit 104 , and a measurement unit 105 . Further, in the present embodiment, a coordinate system is defined in which the axis along the normal direction of the substrate W is the Z axis, and the axes along the directions orthogonal to each other in a plane parallel to the substrate W are the X axis and the Y axis.

The illumination optical system 101 illuminates the original plate R disposed on the illuminated surface (the object surface of the projection optical system 103) using the light (light flux) from the light source 1 . The light source 1 includes, for example, an ultra-high pressure mercury lamp that generates light such as I-line (wavelength 365 nm). However, the light source 1 is not limited, and a KrF excimer laser emitting light of a wavelength of 248 nm, an ArF excimer laser emitting light of a wavelength of 193 nm, or an F ₂ laser emitting light of a wavelength of 157 nm may be Note that the light source 1 may be an EUV light source that generates light (EUV light) having an extreme ultraviolet wavelength of about 11 nm to 14 nm.

On the original plate R, a pattern to be transferred to the substrate W (for example, a circuit pattern) is formed. The original plate R is constituted by using, as a base material, a material that transmits light from the light source 1 (illumination optical system 101), for example, quartz glass. The disk drive unit 102 includes, for example, a movable disk stage that holds the disk R, and a disk drive mechanism that drives the disk stage with respect to the X-axis and the Z-axis.

The projection optical system 103 projects the pattern of the original plate R illuminated by the illumination optical system 101 onto the substrate W. The projection optical system 103 includes an imaging optical system, its front focal point is disposed on a plane (position) on which the disk R is disposed, and its rear focal point is disposed on a plane on which the substrate W is disposed. . In other words, the projection optical system 103 makes the arrangement position of the original plate R and the arrangement position of the substrate W a conjugate relationship.

The substrate W is a substrate onto which the pattern of the original R is transferred, and has a resist (photosensitive material) on its surface. The substrate driving unit 104 includes a movable substrate stage holding the substrate W, and a substrate driving mechanism for driving the substrate stage with respect to the X-axis, Y-axis, and Z-axis (and their rotation directions ωx, ωy, and ωz). includes

The measurement unit 105 includes, for example, a light quantity sensor, and measures the illuminance distribution formed on the surface to be illuminated. In the present embodiment, the measurement unit 105 is disposed on the object plane of the projection optical system 103 , specifically, on the disk stage constituting the disk drive unit 102 .

Hereinafter, the illumination optical system 101 is demonstrated in detail. The illumination optical system 101 includes a first relay lens 3 , a bending mirror M1 , an optical integrator 4 , a second relay lens 5 , and a bending mirror M2 . The first relay lens 3 and the bending mirror M1 constitute the first illumination optical system 10 , and the second relay lens 5 and the bending mirror M2 constitute the second illumination optical system 12 . Light from the first illumination optical system 10 passes through the optical integrator 4 and enters the second illumination optical system 12 .

The elliptical mirror 2 has a first focus and a second focus, and condenses the light from the light source 1 disposed at the first focus to the second focus. The first relay lens 3 includes an imaging optical system, the front-side focus of which is arranged at the second focus of the elliptical mirror 2 , and the rear-side focus of the optical integrator 4 . It is placed on the entrance side. In other words, in the first relay lens 3, the second focus of the elliptical mirror 2 and the incident plane of the optical integrator 4 have a conjugate relationship. As described above, in the present embodiment, the illumination optical system 101 includes the first illumination optical system 10 in which the second focus of the elliptical mirror 2 and the incident surface of the optical integrator 4 have a conjugate relationship. However, the first illumination optical system that does not have such a relationship may be included. In the vicinity of the pupil plane of the first relay lens 3, a wavelength filter (not shown) that blocks light in a specific wavelength region is arranged, and the exposure wavelength (wavelength of light exposing the substrate W) is defined by this wavelength filter. do.

The optical integrator 4 is an internal reflection type optical integrator including an incident surface, a reflection surface, and an exit surface ES. The optical integrator 4 forms a uniform light intensity distribution (illuminance distribution) on the exit surface ES by reflecting the light incident on the incident surface by the reflection surface multiple times. Although the optical integrator 4 has a rectangular shape in the cross section (XY plane) orthogonal to the optical axis AX in this embodiment, it may have another shape (for example, polygon). In addition, the optical integrator 4 is not limited to the internal reflection type optical integrator, A microlens array type optical integrator, such as a fly's eye lens, may be sufficient.

The second illumination optical system 12 illuminates the original plate R using the light from the emission surface ES of the optical integrator 4 . The second relay lens 5 includes an imaging optical system, its front focal point is arranged on the emitting surface ES of the optical integrator 4, and its rear focal point is the surface on which the disk R is arranged. is placed in In other words, in the second relay lens 5, the emission surface ES of the optical integrator 4 and the arrangement surface of the disk R have a conjugate relationship. The second relay lens 5 forms the light intensity distribution (illuminance distribution) of the emitting surface ES of the optical integrator 4 on the arrangement surface of the disk R.

In the exposure apparatus 100 according to the present embodiment, the second illumination optical system 12 includes a light-transmitting optical element 6 functioning as a correction filter for correcting the illuminance distribution on the illuminated surface. have. The optical element 6 is an illuminated surface of the illumination optical system 101 (for example, the surface on which the disk R is arranged), a conjugated surface in a conjugate relationship with the illuminated surface, or an illuminated surface or a conjugated surface. placed in the vicinity of In the present embodiment, the optical element 6 is an illumination optical system 101 such that the optical thin film formed on the surface of the optical element 6 described later in the vicinity of the surface on which the original plate R is arranged faces the original plate R. is disposed on the most projection optical system 103 side surface.

Fig. 2 is a schematic diagram showing the configuration of the optical element 6 of the light transmission type. As shown in Fig. 2, the optical element 6 is formed on at least one surface (surface of the optical element 6) of the base material 7 (base material), and is an optical thin film C that functions (acts) as an antireflection film. has In this embodiment, with respect to an arbitrary location (part) of the optical thin film C having the film thickness (maximum film thickness) D, the optical thin film C is partially removed by the removal amount δ in the thickness direction (Z-axis direction) of the optical thin film C By removing it, the film thickness distribution is formed in the optical thin film surface. In this way, the optical thin film C exists over the surface of the optical element 6 (base material 7), and has a film thickness distribution in this surface. In other words, the optical thin film C includes a portion in the surface of the optical element 6 from which the optical thin film C is partially removed in the thickness direction, and at least a part of the optical thin film C remains in this portion.

The antireflection film as the optical thin film C is constituted by superimposing a plurality of thin films made of materials having different refractive indices on the substrate 7 to lower the reflectance using interference of light to obtain a high transmittance as a whole. For each thin film constituting the antireflection film, the number, material, thickness, etc. of the thin films are usually adjusted so that a predetermined transmittance or reflectance can be obtained, and light interference conditions are optimized. Accordingly, the transmittance or reflectance of the optical thin film C can be changed according to the removal amount δ when the optical thin film C is partially removed in the thickness direction. At this time, the type (film type) of the optical thin film C is not limited only to the dielectric multilayer film, and may be a single layer film.

On the other hand, if the optical thin film C formed on the base material 7 is completely removed in the thickness direction, the part from which the optical thin film C is completely removed in the thickness direction will not function as an antireflection film. However, for the purpose of correcting the illuminance distribution on the illuminated surface, that is, making the illuminance distribution uniform, the removal amount δ of the optical thin film C is the thickness of the outermost thin film among the plurality of thin films constituting the antireflection film. It is good enough to adjust (film thickness distribution). Therefore, in this embodiment, the influence of partial removal in the thickness direction of the optical thin film C on the function as an antireflection film is very small, and therefore it is negligible.

Hereinafter, a manufacturing method for manufacturing the optical element 6 will be described with reference to FIG. 3 . In S01 (first step), an optical thin film C functioning as an antireflection film is formed on the surface of the substrate 7 . As described above, in the optical thin film C formed in S01, the number, material, thickness, etc. of the thin films constituting the optical thin film C are adjusted, and the light interference condition is optimized. In the present embodiment, an optical thin film C having a uniform film thickness D is formed on the surface of the substrate 7 .

In S02 (second process), the optical thin film C formed in S01 is removed in the thickness direction. At this time, even in the region where the optical thin film C is removed, the optical thin film C is removed in the thickness direction so that at least a part of the optical thin film C remains. Therefore, even through S02, in the optical thin film C formed on the surface of the substrate 7 , at least a part of the optical thin film C remains in the thickness direction of the optical thin film C within the surface of the substrate 7 . In the present embodiment, the optical thin film C is partially removed by the removal amount δ in the thickness direction of the optical thin film C with respect to any location of the optical thin film C having the film thickness D. Thereby, as shown in FIG. 2, the transmission type optical element 6 in which the optical thin film C which exists over the surface of the base material 7 and has a film thickness distribution in this surface was formed can be manufactured.

Here, with reference to FIG. 4, the process (step S02) of removing the optical thin film C in the thickness direction is demonstrated in detail.

In S21 (third step), the illuminance distribution formed on the illuminated surface by the light from the illumination optical system 101 in a state in which the transmissive optical element 6 is removed is acquired. Specifically, the measuring unit 105 provided on the disc stage is disposed on the surface on which the disc R is disposed, and the light from the illumination optical system 101 in a state in which the transmissive optical element 6 is removed is measured by the measuring unit 105 ( light intensity sensor) to obtain the illuminance distribution on the illuminated surface. Fig. 5A is a diagram showing an example of the illuminance distribution in the surface to be illuminated obtained in S21. In the illuminance distribution shown in Fig. 5A, the illuminance is locally low at the coordinate a in the surface to be illuminated.

In S22, the transmittance|permeability distribution in the optical thin film C functioning as an antireflection film is designed so that the illuminance distribution in the to-be-illuminated surface acquired in S21 may be canceled. Fig. 5B is a diagram showing an example of the transmittance distribution in the optical thin film C designed in S22. The transmittance distribution shown in Fig. 5B is a transmittance distribution designed for the illuminance distribution shown in Fig. 5A, and has the _{maximum transmittance T max at the coordinate A in the optical thin film plane corresponding to the coordinate a in the illuminated area.}

In S23 (fourth process), the film thickness distribution of the optical thin film C is determined based on the illuminance distribution in the to-be-illuminated surface acquired in S21, and the transmittance|permeability distribution in the optical thin film C designed in S22. At this time, the determination of the film thickness distribution of the optical thin film C determines the portion (coordinates in the optical thin film surface) from which the optical thin film C is to be removed in the surface of the optical element 6 (base 7), and in this portion means to determine the removal amount δ of the optical thin film C. Specifically, as shown in Fig. 5C, multiply the illuminance distribution shown in Fig. 5A and the transmittance distribution shown in Fig. 5B so that the illuminance distribution becomes uniform on the illuminated surface (that is, to realize the transmittance distribution shown in Fig. 5B) ), to determine the film thickness distribution of the optical thin film C. Referring to FIG. 5C , as the film thickness distribution of the optical thin film C, the removal amount δ at the coordinate A in the optical thin film plane having the _{maximum transmittance T max is zero, and the maximum transmittance T max} and each coordinate (position) The removal amount δ is determined according to _{the transmittance difference (T max} -T ) of the transmittance T in the present invention. 6 shows the relationship between the transmittance difference (T _max -T) and the removal amount δ. By acquiring such a relationship in advance, it becomes possible to determine the removal amount δ according to the _{transmittance difference (T max} -T) for each coordinate (position) in the optical thin film surface.

In S24, the optical thin film C is partially removed in the thickness direction with respect to the optical thin film C formed on the base 7 in S01 according to the film thickness distribution (removal amount δ at each coordinate in the optical thin film plane) determined in S23. carry out processing. Thereby, the optical thin film C exists over the surface of the base material 7, and in the surface of the base material 7, the film thickness distribution according to the illuminance distribution which the light transmitted through the optical element 6 should form. will have At this time, the specific method of the removal process performed in S24 is mentioned later.

In S25, the optical element 6 to which the removal process was performed in S24 is incorporated into the illumination optical system 101. As shown in FIG. In the present embodiment, as described above, the optical element 6 is incorporated into the surface of the illumination optical system 101 on the most side of the projection optical system 103 so that the optical thin film C faces the original plate R.

In S26, the illuminance distribution formed on the illuminated surface by the light from the illumination optical system 101 in a state in which the transmissive optical element 6 is incorporated is acquired. Specifically, the measuring unit 105 provided on the disc stage is arranged on the surface on which the disc R is arranged, and the light from the illumination optical system 101 in which the transmissive optical element 6 is incorporated is measured by the measuring unit 105 ( light intensity sensor) to obtain the illuminance distribution on the illuminated surface. Fig. 5D is a diagram showing an example of the illuminance distribution on the illuminated surface obtained in S26. In the illuminance distribution shown in Fig. 5D, the illuminance is uniform within the surface to be illuminated.

In this way, according to the present embodiment, it is possible to manufacture (provide) the transmissive optical element 6 that realizes uniformity of the illuminance distribution on the surface to be illuminated. The exposure apparatus 100 having the illumination optical system 101 in which the transmissive optical element 6 is incorporated can illuminate the original plate R uniformly, and transfer the pattern of the original plate R to the resist on the substrate. It can be performed favorably.

An example of the specific method of the removal process S24 which removes the optical thin film C partially in the thickness direction with reference to FIG. 7 is demonstrated. For the removal processing, a processing technique that removes the optical thin film C in the thickness direction in such a portion by irradiating an ion beam to a portion to be removed, so-called IBF (Ion Beam Figuring), may be used.

Fig. 7 is a schematic diagram showing the configuration of an ion beam processing apparatus 200 for realizing IBF. The ion beam processing apparatus 200 includes a chamber 21 for maintaining a vacuum state, an ion beam generating unit 22 , a driving stage 24 , and a current density measuring unit 25 . The ion beam generating unit 22 , the driving stage 24 , and the current density measuring unit 25 are provided inside the chamber 21 .

The ion beam 23 from the ion beam generator 22 is applied to the transmissive optical element 6 as a workpiece held (installed) on the driving stage 24 , specifically, to the optical thin film C formed on the substrate 7 . is investigated A removal process for partially removing the optical thin film C in the thickness direction is performed by scanning the driving stage 24 and irradiating an arbitrary portion (position) of the optical thin film C with the ion beam 23 .

By irradiating the ion beam 23 from the ion beam generating unit 22 to the current density measuring unit 25 provided in the driving stage 24 , it is possible to measure the beam profile of the ion beam 23 . By optimizing the beam profile of the ion beam 23 measured by the current density measuring unit 25 for the processing conditions such as the removal amount δ (processing amount) of the optical thin film C and the processing pitch, high-precision removal processing can be realized.

Transmissive type optics that use such an ion beam processing apparatus 200 for the removal processing (S24) to correct unevenness of the illuminance distribution on the illuminated surface with high precision, that is, achieve uniformity of the illuminance distribution on the illuminated surface. The device 6 can be manufactured (provided).

Another example of the specific method of the removal process (S24) which removes the optical thin film C partially in the thickness direction with reference to FIG. 8 is demonstrated. In the removal processing, a processing technique that removes the optical thin film C in the thickness direction in such a portion by polishing a portion from which the optical thin film C is to be removed using a magnetic fluid containing abrasive particles, so-called MRF (Magneto- Rheological Finishing) may be used. MRF is a high-precision polishing technique using magnetic force.

Specifically, as shown in FIG. 8 , a magnetic fluid 31 containing abrasive particles is flowed between the optical thin film C formed on the substrate 7 and the stage 32 . Then, when a magnetic force 34 is applied to the magnetic fluid 31 from the electromagnet 33 , magnetically abrasive particles contained in the magnetic fluid 31 under the influence of the magnetic force 34 are formed on the surface of the optical thin film C. to contact At this time, by driving the stage 32 , the magnetic fluid 31 flows through the surface of the optical thin film C, and the optical thin film C is polished by the magnetic fluid 31 . By controlling the magnetic force 34 by the electromagnet 33, highly accurate removal processing can be implement|achieved.

By using this high-precision polishing technique for the removal processing (S24), a transmissive optical element that corrects with high precision the non-uniformity of the illuminance distribution on the illuminated surface, that is, achieves uniformity of the illuminance distribution on the illuminated surface. (6) can be manufactured (provided).

Another example of the specific method of the removal process S24 for partially removing the optical thin film C in the thickness direction is described with reference to FIGS. 9A to 9D. For the removal processing, a processing technique in which the optical thin film C is removed in the thickness direction by etching the portion from which the optical thin film C is to be removed may be used, for example, an etching technique using a resist.

Specifically, first, as shown in FIG. 9A , a resist 41 is applied on the optical thin film C formed on the substrate 7 . Next, as shown in Fig. 9B, the resist 41 in the portion 42 is removed by exposing and developing the portion 42 from which the optical thin film C is to be removed using an exposure apparatus or the like. Next, as shown in Fig. 9C, the optical thin film C in the portion 42 is removed (shaved) by etching the portion 42 . Then, as shown in Fig. 9D, the resist 41 applied on the optical thin film C is peeled off. By passing the steps shown in Figs. 9A to 9D, it is possible to realize high-precision removal processing for any part of the optical thin film C. As shown in Figs.

By using this etching technique for the removal processing (S24), the transmissive optical element 6 which corrects the unevenness of the illuminance distribution on the illuminated surface with high precision, that is, achieves uniformity of the illuminance distribution on the illuminated surface. ) can be manufactured (provided).

Another example of the specific method of the removal process (S24) of partially removing the optical thin film C in the thickness direction is demonstrated with reference to FIGS. 10A-10C. You may use the processing technique which makes the release agent act on the part from which the optical thin film C should be removed, and removes the optical thin film C in such a part in the thickness direction for a removal process. As a release agent, HF (hydrofluoric acid) is used, for example.

Specifically, first, as shown in FIG. 10A , a mask 51 including an opening 52 is disposed on the optical thin film C formed on the substrate 7 . Next, as shown in Fig. 10B, the release agent 53 is poured into the opening portion 52 of the mask 51 to remove the optical thin film C in the portion exposed to the opening portion 52 (peeling). )do. Then, as shown in Fig. 10C, the mask 51 disposed on the optical thin film C is removed. By passing the steps shown in Figs. 10A to 10C, it is possible to realize high-precision removal processing for any part of the optical thin film C. As shown in Figs.

Transmissive optical element that corrects the unevenness of the illuminance distribution on the illuminated surface with high precision, that is, achieves uniformity of the illuminance distribution on the illuminated surface, by using such a technique using the release agent for the removal processing (S24). (6) can be manufactured (provided).

The manufacturing method of the article in embodiment of this invention is suitable for manufacture of articles|goods, such as a semiconductor element, a flat panel display, a liquid crystal display element, MEMS, for example. This manufacturing method includes a step of exposing a substrate coated with a photosensitizer using the above-described exposure apparatus 100 and a step of developing the exposed photosensitive agent. In addition, an etching process or an ion implantation process is performed on the substrate using the developed photosensitizer pattern as a mask, and a circuit pattern is formed on the substrate. These steps of exposure, development, etching, etc. are repeated to form a circuit pattern composed of a plurality of layers on the substrate. In a post process, dicing (processing) is performed with respect to the board|substrate on which the circuit pattern was formed, and chip mounting, bonding, and inspection process are performed. In addition, such a manufacturing method may include other well-known processes (oxidation, film formation, vapor deposition, doping, planarization, resist stripping, etc.). The method for manufacturing an article according to the present embodiment is advantageous compared to the prior art in at least one of the performance, quality, productivity, and production cost of the article.

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. Accordingly, the claims are attached to clarify the scope of the invention.

Claims (12)

A manufacturing method for manufacturing a light-transmitting optical element, comprising:
A first step of forming an anti-reflection film on the surface of the optical element;
a second step of removing the antireflection film formed in the first step in a thickness direction of the antireflection film;
In the second step, the antireflection film is removed in the thickness direction so that at least a part of the antireflection film remains even in a region where the antireflection film is removed.
The method of claim 1,
In the second step, the antireflection film is removed in the thickness direction by irradiating a portion in the surface where the antireflection film is to be removed by irradiating it with an ion beam.
The method of claim 1,
In the second step, the portion in the surface where the antireflection film is to be removed is polished using a magnetic fluid containing abrasive particles to remove the antireflection film in the portion in the thickness direction. manufacturing method.
The method of claim 1,
In the second step, by etching a portion in the surface where the antireflection film is to be removed, the antireflection film in the portion is removed in the thickness direction.
The method of claim 1,
In said 2nd process, the said antireflection film in the said part is removed in the said thickness direction by making a release agent act on the part from which the said antireflection film should be removed in the said surface, The said manufacturing method characterized by the above-mentioned.
The method of claim 1,
The optical element is incorporated into an optical system for illuminating a surface to be illuminated;
a third step of acquiring an illuminance distribution formed on the illuminated surface by light from the optical system in a state in which the optical element is removed;
A manufacturing method further comprising a fourth step of determining a portion in the surface where the antireflection film is to be removed and an amount of the antireflection film removed in the portion based on the illuminance distribution.
7. The method of claim 6,
In the fourth step, the portion and the removal amount are determined so that an illuminance distribution that cancels the illuminance distribution is formed on the illuminated surface by the light transmitted through the optical element.
An exposure apparatus for exposing a substrate through an original plate, comprising:
an illumination optical system for illuminating the original plate;
a projection optical system for projecting the pattern of the original illuminated by the illumination optical system onto the substrate;
The illumination optical system includes a transmissive optical element having an antireflection film formed on its surface,
The anti-reflection film is present in the surface, and an illuminance distribution formed on the surface on which the disc is arranged by the light transmitted through the optical element from the illumination optical system in a state in which the optical element is removed. An exposure apparatus characterized by having a film thickness distribution in the surface so as to form an illuminance distribution that cancels the .
9. The method of claim 8,
The exposure apparatus according to claim 1, wherein the optical element is disposed on a surface to be illuminated of the illumination optical system or a conjugated surface of the surface to be illuminated.
9. The method of claim 8,
The exposure apparatus according to claim 1, wherein the optical element is disposed on a surface of the illumination optical system closest to the projection optical system so that the antireflection film faces the original plate.
A step of exposing the substrate using the exposure apparatus according to claim 8;
developing the exposed substrate;
A method for manufacturing an article, comprising a step of manufacturing the article from the developed substrate.
A light-transmitting optical element, comprising:
It has an antireflection film formed on the surface of the optical element,
The antireflection film is present over the surface and has a film thickness distribution in the surface according to the illuminance distribution to be formed by the light transmitted through the optical element.

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