JP2001124968A - Optical element holding method, optical element holding mechanism and exposure device utilizing optical element group held by optical element holding mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical element holding method and an optical element holding mechanism, capable of suppressing deformation of a holding member for holding an optical element, highly accurately positioning the optical element at a prescribed position and eliminating deformation of the surface shape of the optical element and deterioration of optical characteristics based on it. SOLUTION: In this optical element holding mechanism constituted of a cell 2 for supporting and positioning the outer peripheral part of the optical element 1 and a lens barrel 5 for supporting and positioning the cell 2 at a prescribed location via a spacer 7, the cell 2 is formed of highly rigid ceramics, the reference members 3a-3d of superior machinability, such as brass are joined to a reference part for performing positioning by being abutted against an abutting part (a), the lens barrel 5 and the spacer 7, etc., and a highly rigid structure capable of highly accurate working is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element holding method and an optical element holding mechanism for positioning an optical element such as a lens or a mirror at a predetermined position, and an optical element group held by the optical element holding mechanism. The present invention relates to an exposure apparatus to be used.

[0002]

2. Description of the Related Art As a method of positioning an optical element such as a lens or a mirror at a predetermined position, there is a method of assembling a lens barrel by ball pushing, throwing, and the like. In an optical system that requires high-precision positioning by an optical element, an assembling method using a cell structure is employed.

Hereinafter, a lens barrel structure having a cell structure will be described with reference to FIG. In FIG. 7, reference numeral 102 denotes a ring-shaped holding member (hereinafter, referred to as a cell) for holding the lens 101 constituting the refraction type projection optical system, which is usually made of a free-cutting material such as aluminum or brass. ing.
Reference numeral 105 denotes a lens barrel for coaxially fixing the plurality of cells 102 with predetermined positional accuracy, and reference numeral 106 denotes a holder for abutting the cell 102 against a protrusion 105 a provided at a lower portion of the lens barrel 105 and fixing the cell 102. It is a ring.

[0004] The lens 101 and the cell 102 are
One optical axis and the outer shape of the cell 102 are caulked so as to have a predetermined coaxiality, and the inner diameter of the lens barrel 105 for fixing the plurality of cells 102 inside has the desired coaxiality. The cells 102 are processed with a predetermined cylindricity so that they can be arranged, and the plurality of cells 102 are stacked with a spacer 107 having a height determined so that the interval between the lenses 101 has a desired accuracy.

[0005] The plurality of lenses 101 constituting the projection optical system are positioned in the lens barrel 105 while maintaining a desired interval and coaxiality with each other.

[0006]

By the way, in the prior art as described above, it is common to use a metal material as a material of a cell holding a lens from the viewpoint of machinability. However, the cell receives an external force from the lens barrel for positioning and fixing in the lens barrel, and this external force causes a small elastic deformation of a contact portion between the lens and the cell, thereby distorting the surface shape of the lens. Furthermore, since the cell is deformed by gravity other than the external force from the lens barrel, there is a problem that the surface shape of the lens changes due to the deformation of the cell by its own weight, and the optical characteristics are deteriorated.

In order to deal with these problems with a single material, a high-rigidity material is generally used. However, a high-rigidity material has a remarkably poor workability, and requires a long time for high-precision processing and correction, and a high productivity. Is worsened.

In view of the foregoing, the present invention has been made in view of the above-mentioned unsolved problems of the prior art, and enables a holding member for holding an optical element such as a lens to be processed with high rigidity and high precision. As a simple structure, the deformation of the holding member is suppressed and the optical element can be positioned at a predetermined position with high accuracy.
Provided is an optical element holding method and an optical element holding mechanism that can prevent a change in the surface shape of an optical element and deterioration of optical characteristics based on the change in the surface shape, and further provide an optical element held by the optical element holding mechanism. It is an object of the present invention to provide an exposure apparatus using a group of elements.

[0009]

In order to achieve the above object, an optical element holding method according to the present invention comprises a first holding member for supporting an optical element and a first holding member for supporting the first holding member at a predetermined position. In the optical element holding method for holding the optical element at a predetermined position using the second holding member, the first holding member is formed of a highly rigid material, and the optical element and / or the second A reference member having excellent machinability is joined to a portion of the first holding member that contacts the holding member.

In the optical element holding method according to the present invention, it is preferable that the first holding member supports and positions an outer peripheral portion of the optical element.

In the optical element holding method according to the present invention, it is preferable that the reference member is cut after being joined to the first holding member.

In the optical element holding method according to the present invention, it is preferable that the first holding member is formed of ceramics or a steel material.
Preferably, aluminum, copper or stainless steel is used.

In the optical element holding method according to the present invention, it is preferable that each of the plurality of optical elements is held at a predetermined position.

Further, the optical element holding mechanism of the present invention is an optical element holding mechanism for holding an optical element at a predetermined position, wherein the first holding member supports the optical element;
A second holding member for supporting the first holding member at a predetermined location, wherein the first holding member is formed of a highly rigid material, and the optical element and / or the second
A reference member having excellent machinability is joined to a portion of the first holding member abutting on the holding member.

In the optical element holding mechanism of the present invention, it is preferable that the first holding member is configured to support and position an outer peripheral portion of the optical element.

In the optical element holding mechanism according to the present invention, it is preferable that the first holding member is formed of ceramics or a steel material.
Preferably, aluminum, copper or stainless steel is used.

In the optical element holding mechanism of the present invention, the reference member is joined to the first member by an adhesive, brazing, plating, thermal spraying, vapor deposition, or screw connection. Is preferred.

In the optical element holding mechanism of the present invention, it is preferable that each of the plurality of optical elements is held at a predetermined position.

The exposure apparatus of the present invention uses an optical element group using the above-described optical element holding mechanism to expose and transfer an original pattern onto a substrate at a predetermined magnification by illumination light emitted from a light source. It is characterized by doing.

Further, in the device manufacturing method of the present invention, a step of preparing the above-described exposure apparatus, a step of applying a photosensitive material to the substrate, a step of exposing a circuit pattern to the substrate using the exposure apparatus, And a step of developing the formed substrate.

[0021]

According to the present invention, a cell for supporting and positioning an outer peripheral portion of an optical element such as a lens is made of a material having a high specific rigidity such as ceramics or a steel material, and is cut at a reference portion for positioning the cell. By joining a reference member made of brass, aluminum, copper, etc., which has excellent workability, high rigidity is achieved by utilizing the characteristics of both the material such as ceramics with high specific rigidity and the reference member with excellent machinability. It has a cell structure that enables high-precision processing and suppresses cell deformation with a highly rigid material, eliminating distortion and deformation of the surface shape of the optical element.Furthermore, the optical element can be accurately positioned at a predetermined place. This makes it possible to prevent optical characteristics from deteriorating. In addition, the reference member having excellent cutting workability makes it easy to cut a portion serving as a positioning reference, and can improve the accuracy of the reference position. Further, since the reference member for positioning can be replaced, The productivity of processing correction can be improved.

Further, by applying the optical element group held by the optical element holding mechanism of the present invention to an exposure apparatus,
Since the deformation of the cell can be suppressed, the surface shape of each optical element can be kept in the state before bonding, the optical characteristics of the optical system can be prevented from deteriorating, and high-accuracy exposure transfer can be performed. Become.

[0023]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an end view schematically showing a projection optical system to which an embodiment of an optical element holding mechanism according to the present invention is applied, in which the direction of gravity coincides with the optical axis. In the -Z direction.

In FIG. 1, reference numeral 1 denotes an optical element such as a lens constituting a refraction type projection optical system, and 2 denotes a ring-shaped cell for supporting and positioning the outer peripheral portion of the optical element 1. A portion made of alumina ceramics (Al ₂ O ₃ ) and supporting and contacting the outer peripheral portion of the optical element 1 (this contact portion is indicated by a in FIG. In the portion, the upper surface portion, and the lower surface portion, a reference portion for abutting against another member for positioning is made of a brass member (hereinafter referred to as a brass member or a reference member) having excellent cutting workability, respectively. 3d is joined by an adhesive. The optical element 1 and the cell 2 are joined so that the optical axis of the optical element 1 and the outer diameter of the cell 2 have a predetermined coaxiality.

Reference numeral 5 denotes a lens barrel for coaxially fixing the plurality of cells 2 with a predetermined positional accuracy. The inner diameter of the lens barrel is such that the cells 2 can be arranged with a desired coaxiality.
It is formed with a predetermined cylindricity. 6 is a plurality of cells 2
Is a press ring for abutting and fixing a projection 2a on the lower part of the lens barrel 5, and a spacer 7 for positioning the cells 2 in the optical axis direction at predetermined intervals in the lens barrel 5. In addition, the cells 2 are arranged at three positions at a pitch of 120 degrees on the circumference so as to support the cells 2 at three points.

As described above, the plurality of cells 2 for joining and supporting the plurality of optical elements 1 constituting the projection optical system to the respective barrel portions a are provided within the lens barrel 5 via the spacers 7 at predetermined intervals. The projection 5 of the lens barrel 5 is stacked with
a and the holding ring 6 are positioned and fixed at predetermined locations. Thereby, the plurality of optical elements 1
Are positioned and held in the lens barrel 5 while maintaining a desired interval and coaxiality with each other. In the cell 2 made of alumina ceramics, a portion that comes into contact with the optical element 1, the lens barrel 5, the spacer 7, the holding ring 6, and the like is a portion serving as a reference for positioning the cell 2; Brass members 3a to 3d excellent in cutting workability are joined, and these reference members 3a to 3d are finished to predetermined dimensional accuracy by processing such as cutting or grinding in advance.

As described above, in this embodiment, the cell 2 for supporting the outer peripheral portion of the optical element 1 and positioning it in the lens barrel 5 is made of alumina ceramics.
A structure in which the brass members 3a to 3d having excellent machinability are joined to a reference portion in contact with the lens barrel 5, the spacer 7, and the like at the body attached portion a of the cell 2 and the outer portion, the upper portion, and the lower portion of the cell 2. The characteristics of this structure will be described below.

When the alumina ceramic cell used in this embodiment and the brass cell conventionally and generally used are supported at three points, how these cells deform their body parts by their own weights. Was analyzed by the finite element method (both cell shapes were φ200 m
m, h: 20 mm) However, in the case of a brass cell, the body-attached portion of the cell is deformed by about 0.31 μm (in the −Z direction) at a portion far from the support portion relative to a portion near the support portion. However, in a cell made of alumina ceramics, the amount of its own weight deformation is about 0.04 μm at the maximum (-Z direction).
Met. Further, when an optical element (lens) made of quartz (SiO ₂ ) is supported at three points on its outer periphery, how the optical element is deformed by its own weight is also analyzed by the finite element method. When the outer peripheral portion of the optical element is supported at three points, a portion far from the support portion is deformed by about 0.26 μm (in the −Z direction) with respect to a portion near the support portion.
Therefore, when the optical element is supported by the brass cell supported at three points, the brass cell deforms by its own weight more than the optical element.
It can be seen that a deformation of about 0.26 μm occurs as in the case of supporting at a point. On the other hand, when the optical element is supported by the alumina ceramic cell supported at three points, the outer peripheral portion of the optical element is not freely deformed by its own weight, and it is found that the deformation is suppressed to 0.04 μm or less at the maximum. did.

This is because alumina ceramics used as a material of the cell has a higher Young's modulus than brass (alumina ceramics: 3.4 × 10 ¹¹ Pa, brass: 1.0).
× 10 ¹¹ Pa) and low specific gravity (alumina ceramics: 3.8, brass: 8.5).

In order to minimize the deformation of the optical element by its own weight, it is desirable to support the outer peripheral part of the optical element uniformly over its entire circumference. For this purpose, it is necessary to form the body-attached part of the cell on the same plane as much as possible. There is. When the cell body is formed by cutting or grinding, the amount of deformation of the cell due to the pressing force of the blade is smaller for ceramics than for brass. Can be performed with higher accuracy.

Further, in this embodiment, each of the portions where the alumina ceramic cell 2 comes in contact with the optical element 1, the lens barrel 5, the spacer 7 and the like is provided with positioning reference members 3a to 3d as free-cutting members. Since brass is joined, it is easy to obtain dimensional accuracy at the reference position. That is, although ceramics are lightweight and highly rigid and are excellent as a structural body, they have a problem that cutting and grinding take time, but as in this embodiment,
By joining a free-cutting brass member to a portion that requires post-processing in order to obtain dimensional accuracy at the reference position, the processing time can be significantly reduced. Also, brass is
Since the cutting process can be performed without using the cutting oil, the optical element 1 and the cell 2 are combined, and after the optical element 1 is contaminated with the cutting oil or the like, the optical axis reference of the optical element 1 can be performed. It is also possible to cut the brass members 3a to 3d serving as a position reference for.

In this embodiment, the optical element is made of quartz (S
iO ₂ ), but alumina ceramics
Lower linear expansion coefficient than brass (alumina ceramics:
7.1 × 10 ⁻⁶ / K, brass: 17.5 × 10 ⁻⁶ / K),
Since the coefficient of linear expansion of quartz is close to that of quartz (0.5 × 10 ^-6 / K), the cell made of ceramics has a higher optical expansion due to the difference in linear expansion between the cell and the optical element when the temperature changes than the cell made of brass. There is also an effect that the element receives less stress from the cell.

In this embodiment, alumina ceramic was used as the cell material. However, not only a material having a high specific rigidity but also a linear expansion coefficient close to the linear expansion coefficient of the optical element material constituting the optical system was used. By selecting a ceramic having the following, optical performance can be stably maintained even when the environmental temperature changes.

In the above-described embodiment, an adhesive is used for joining the ceramics and the brass member as the reference member for positioning. However, the joining may be performed by brazing.
As shown in FIG. 2, a brass member 13 (13a to 13d) as a reference member is screwed to a screw 14 (14a
14d), it is also possible to detachably fasten to the ceramic cell 2. By fastening with the screw 14 in this manner, the brass member 13 can be easily detached from the cell 2. When the brass member as the reference member is processed and modified, if the brass member is joined by adhesive or brazing as described above, the brass member is peeled from the cell with a solvent, etc., and unprocessed new brass After rejoining the members, processing such as cutting of a brass member serving as a positioning reference is performed. However, when the brass member 13 is fastened with the screw 14 as shown in FIG. Remove the screws 14 (14a to 14d) and remove the brass member 13.
After removing (13a to 13d) from the cell 2, a new unprocessed brass member 13 can be attached with the screw 14, and processing correction such as cutting of the brass member serving as a position reference can be performed easily and easily. It becomes possible.

Further, as a method of joining a brass member as a reference member for positioning to the cell, as shown in FIG. 3, a brass film 23 (see FIG. 3) is formed on the surface of the ceramic cell 2 by plating, thermal spraying, stamping, vapor deposition, or the like. 23a-23
d) can also be formed. Thus, the formation of the brass film 23 (23a to 23d) on the ceramic cell 2 is particularly effective when the machining allowance for cutting the positioning reference is several μm to several tens μm. Thus, the brass film 23 (23a to 23a)
By forming d), it is possible to easily perform processing such as cutting of a brass film serving as a position reference, which has the characteristics of light weight and high rigidity of ceramics. The same operation and effect as those of the first embodiment can be obtained.

In the brass member to be joined to the cell,
As shown in FIG. 4, a brass member (a member corresponding to 3 a in FIG. 1) on the body of the cell 2 and a brass member on the other outer periphery of the cell 2 (a member corresponding to 3 b to 3 d in FIG. 1) The brass member 33 can be joined to the entire outer periphery of the cell 2 in such a manner that the optical element 1 is irradiated with illumination light. The heat can be efficiently transmitted to the lens barrel 5 via the brass member 33 without accumulating heat in the element 1, and it is possible to prevent deterioration of the optical characteristics due to thermal aberration.

Further, the material of the reference member to be joined to the portion serving as the positioning reference of the cell 2 is not limited to the above-mentioned brass, and for example, a material having excellent machinability such as aluminum, copper, and stainless steel is used. It can also be used.

Next, another embodiment of the present invention will be described with reference to FIG. In the present embodiment, the optical element holding mechanism including the optical element and the cell, the lens barrel, the holding ring, the spacer, and the like is configured in the same manner as in the above-described embodiment, and the same members as in the above-described embodiment. Are denoted by the same reference numerals, and a detailed description thereof will be omitted.

In this embodiment, a steel material is used as the material of the cell 42, and the positioning reference member 43 (43a) is used.
43d) uses brass, and the joining of both uses brass thermal spraying. The material of the cell 42 may be selected from materials having a higher specific rigidity than the reference member 43 (43a to 43d), and the cell 42 may be joined by another method as described above.

Although the cell 42 made of a steel material or the like used in the present embodiment is inferior in rigidity as compared with the ceramic cell in the above-described embodiment, it is intended to greatly reduce the material cost. In addition, it is excellent in terms of processing, and for example, it is easy to perform additional processing such as directly tapping a cell or to produce a complicated shape. Also, by using a low thermal expansion material such as zero joule, it is possible to further reduce the thermal expansion difference between the optical element and the cell as compared with ceramics.

Next, an exposure apparatus to which a projection optical system constituted by an optical element group held by the above-described optical element holding mechanism is applied will be described. FIG. 6 is a schematic configuration diagram of the exposure apparatus. The same members as those in the above-described embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 6, the projection optical system 50 comprises an optical element 1 such as a lens, a cell 2 to which positioning reference members 3a to 3d are joined, a lens barrel 5, a spacer 7, a holding ring 6, and the like. Reference numeral 51 denotes an illumination optical system; 52, a reticle as an original on which a pattern to be transferred is formed; 53, a reticle stage for holding the reticle 52; 54
Reference numeral 55 denotes a surface plate for setting the projection optical system 50 at a predetermined position of the exposure apparatus main body. Reference numeral 55 denotes a wafer as a substrate onto which a pattern is transferred, and reference numeral 56 denotes a wafer stage for holding the wafer 55.

The reticle 52 on which the pattern to be transferred is formed is placed on a reticle stage 53 and irradiated with illumination light guided through the illumination optical system 51. The exposure light transmitted through the reticle 52 is irradiated onto the wafer 55, which is a substrate to be processed, at a predetermined magnification via the projection optical system 50, and the pattern of the reticle 52 is exposed and transferred onto the wafer 55.

According to the exposure apparatus configured as described above, the cell 2 that supports and positions the outer peripheral portion of the optical element 1
By using ceramics or a steel material, the deformation of the cell 2 can be suppressed, the surface shape of the optical element 1 can be kept in a state before joining, and the optical characteristics of the projection optical system 50 can be prevented from deteriorating. It is possible to perform exposure transfer with high accuracy.

Next, an embodiment of a method of manufacturing a semiconductor device using the above-described exposure apparatus will be described.

FIG. 8 shows a flow of manufacturing a semiconductor device (a semiconductor chip such as an IC or an LSI, or a liquid crystal panel or a CCD). In step 1 (circuit design), a pattern of a semiconductor device is designed. Step 2 is a process for making a mask on the basis of the circuit pattern design. In step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is called a pre-process, and an actual circuit is formed on the wafer by lithography using the prepared mask and wafer. Step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). . In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 9 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 1
In 5 (resist processing), a photosensitive material is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer.

By using the manufacturing method of this embodiment, a highly integrated semiconductor device, which was conventionally difficult to manufacture, can be manufactured stably at low cost.

[0050]

As described above, according to the present invention,
The cell that supports and positions the outer periphery of the optical element such as a lens is made of a material with high specific rigidity, such as ceramics or steel. Alternatively, by joining a positioning reference member formed of copper or the like,
By utilizing the characteristics of both a material such as ceramics having high specific rigidity and a reference member having excellent machinability, a cell structure having high rigidity and capable of high-precision processing can be obtained. That is, the deformation of the cell can be suppressed by the high rigidity material,
It is possible to eliminate distortion and deformation of the surface shape of the optical element and accurately position the optical element at a predetermined place,
Optical characteristics can be prevented from deteriorating, and the positioning reference member with excellent cutting workability makes it easy to cut the position reference position, and furthermore, the reference member can be easily detached from the cell. By doing so, the member can be replaced, and productivity such as processing correction can be improved.

Further, by applying the optical element group held by the optical element holding mechanism of the present invention to an exposure apparatus,
Since the deformation of the cell can be suppressed and the positional accuracy can be improved, the surface shape of each optical element can be kept in the state before joining, and the optical characteristics of the optical system can be prevented from deteriorating, and high precision exposure transfer Can be performed.

[Brief description of the drawings]

FIG. 1 is an end view schematically showing a projection optical system to which an embodiment of an optical element holding mechanism according to the present invention is applied.

FIG. 2 is a schematic end view showing an example in which a positioning reference member is detachably fastened to a cell by a screw in the optical element holding mechanism of the present invention.

FIG. 3 is a schematic end view showing an example in which a brass film as a reference member for positioning is formed on a ceramic cell by plating or thermal spraying in the optical element holding mechanism of the present invention.

FIG. 4 is a schematic end view showing an example in which a positioning reference member is integrated with a barrel portion of a cell and another outer peripheral portion in the optical element holding mechanism of the present invention.

FIG. 5 is an end view schematically showing a projection optical system to which another embodiment of the optical element holding mechanism of the present invention is applied.

FIG. 6 is a schematic configuration diagram of an exposure apparatus to which a projection optical system including a group of optical elements held by an optical element holding mechanism of the present invention is applied.

FIG. 7 is an end view schematically showing a lens barrel structure using a conventional cell structure.

FIG. 8 is a flowchart showing a semiconductor device manufacturing process.

FIG. 9 is a flowchart showing a wafer process.

[Explanation of symbols]

 Reference Signs List 1 optical element (lens) 2 cell (made of alumina ceramic) 3 (3a to 3d) reference member (brass member) 5 lens barrel 6 holding ring 7 spacer 13 (13a to 13d) reference member (brass member) 14 (14a to 14d) ) Screw 23 (23a to 23d) Reference member (brass film) 33 Reference member (brass member) 42 Cell (made of steel) 43 (43a to 43d) Reference member (brass member) 50 Projection optical system 51 Illumination optical system 52 Original plate (Reticle) 53 Reticle stage 54 Surface plate 55 Substrate (wafer) 56 Wafer stage

Claims (18)

[Claims] An optical element for holding an optical element at a predetermined position by using a first holding member for supporting the optical element and a second holding member for supporting the first holding member at a predetermined position. In the holding method, the first holding member is formed of a material having high rigidity, and a portion of the first holding member that comes into contact with the optical element and / or the second holding member has excellent cutability. An optical element holding method comprising joining members. 2. The optical element holding method according to claim 1, wherein the first holding member supports and positions an outer peripheral portion of the optical element. 3. The optical element holding method according to claim 1, wherein the reference member is cut after being joined to the first holding member. 4. The optical element holding method according to claim 1, wherein said first holding member is formed of ceramics. 5. The optical element holding method according to claim 1, wherein the reference member is made of brass, aluminum, copper, or stainless steel. 6. The method according to claim 1, wherein the first holding member is formed of a steel material.
Item 6. The optical element holding method according to item 1. 7. The method according to claim 6, wherein the reference member is made of brass, aluminum, or copper. 8. The optical element holding method according to claim 1, wherein each of the plurality of optical elements is held at a predetermined position. 9. An optical element holding mechanism for holding an optical element at a predetermined position, wherein the first holding member supports the optical element and the second holding member supports the first holding member at a predetermined position. And the first holding member is formed of a material having high rigidity, and the portion of the first holding member that contacts the optical element and / or the second holding member has excellent machinability. An optical element holding mechanism, wherein the reference member is joined. 10. The optical element holding mechanism according to claim 9, wherein the first holding member supports and positions an outer peripheral portion of the optical element. 11. The optical element holding mechanism according to claim 9, wherein said first holding member is formed of ceramics. 12. The reference member is made of brass, aluminum,
The optical element holding mechanism according to any one of claims 9 to 11, wherein the optical element holding mechanism is made of copper or stainless steel. 13. The optical element holding mechanism according to claim 9, wherein the first holding member is formed of a steel material. 14. The optical element holding mechanism according to claim 13, wherein the reference member is made of brass, aluminum, or copper. 15. The reference member is bonded by an adhesive, by brazing, by plating, by thermal spraying, by vapor deposition,
Alternatively, the first member is joined to the first member by a screw connection.
Item 6. The optical element holding mechanism according to Item 1. 16. The optical element holding mechanism according to claim 9, wherein each of the plurality of optical elements is held at a predetermined position. 17. A pattern of an original plate at a predetermined magnification by illumination light emitted from a light source, utilizing an optical element group using the optical element holding mechanism according to claim 9. An exposure apparatus, which performs exposure transfer on the top. 18. A step of preparing the exposure apparatus according to claim 17, a step of applying a photosensitive material to the substrate, a step of exposing a circuit pattern to the substrate by using the exposure apparatus, and a step of exposing the exposed substrate. Developing the device.