阅读说明：本技术 曝光用镜、曝光用镜的制造方法以及具备该曝光用镜的曝光装置 (Exposure mirror, method for producing exposure mirror, and exposure apparatus provided with exposure mirror ) 是由 麻籍文 吉本芳幸 于 2020-04-07 设计创作，主要内容包括：本发明提供能够以廉价的结构检测损伤、应变量等的镜的状态的曝光用镜、曝光用镜的制造方法、以及具备该曝光用镜的曝光装置。曝光用镜具备：反射膜,其形成于板状玻璃的表面侧,能够反射来自光源的光；以及导电性的成膜图案,其在板状玻璃的背面侧以比反射膜薄且从一端部到另一端部连续的方式成膜,成膜图案在曝光用镜损伤时断裂从而能够检测曝光用镜的损伤。(The invention provides an exposure mirror capable of detecting the state of the mirror such as damage and strain with a cheap structure, a method for manufacturing the exposure mirror, and an exposure device with the exposure mirror. The exposure mirror includes: a reflective film formed on the surface side of the plate glass and capable of reflecting light from the light source; and a conductive film formation pattern which is formed on the back surface side of the plate glass so as to be thinner than the reflective film and to be continuous from one end portion to the other end portion, wherein the film formation pattern is broken when the exposure mirror is damaged, and damage of the exposure mirror can be detected.)

1. An exposure mirror for reflecting light from a light source, the exposure mirror comprising:

a reflective film formed on a surface side of the plate glass and capable of reflecting light from the light source; and

and a conductive film formation pattern formed on the back surface side of the plate-shaped glass so as to be thinner than the reflective film and to be continuous from one end portion to the other end portion.

2. The exposure mirror according to claim 1,

the film formation pattern is broken when the exposure mirror is damaged, and damage of the exposure mirror can be detected.

3. The exposure mirror according to claim 1 or 2,

the film formation pattern is formed along an outer peripheral portion of the plate glass.

4. The exposure mirror according to claim 1 or 2,

the film formation pattern is formed continuously from the one end portion to the other end portion through the outer peripheral portion and the inner portion of the plate glass.

5. The exposure mirror according to claim 1 or 2,

the film formation pattern is formed by connecting a plurality of patterns having different resistance values in parallel from the one end portion to the other end portion.

6. The exposure mirror according to claim 1 or 2,

when stress is applied to the film formation pattern, the resistance value of the film formation pattern changes, and the amount of strain of the exposure mirror can be detected.

7. The exposure mirror according to any one of claims 1 to 6,

the reflective film and the film formation pattern are formed of the same metal material.

8. A method for manufacturing an exposure mirror for reflecting light from a light source, the method comprising:

a step of shielding the periphery of a conductive film formation pattern that continues from one end portion to the other end portion on the back surface side of a plate-shaped glass; and

and depositing or sputtering a metal material from the front surface side of the plate glass to form a reflective film capable of reflecting light from the light source on the front surface side of the plate glass and to form the film formation pattern on the back surface side of the plate glass.

9. An exposure apparatus, characterized in that,

provided is an illumination device provided with: a light source; an integrator that uniformly emits light from the light source; and the exposure mirror according to any one of claim 1 to claim 7, which reflects the light emitted from the integrator,

the light from the illumination device is irradiated onto a workpiece through a mask, and an exposure pattern of the mask is exposed and transferred to the workpiece.

10. The exposure apparatus according to claim 9,

the exposure mirror includes a mirror bending mechanism that is provided on a back surface side of the exposure mirror and is capable of changing a curvature of the exposure mirror.

Technical Field

The present invention relates to an exposure mirror, a method for manufacturing an exposure mirror, and an exposure apparatus including the exposure mirror, and more particularly, to an exposure mirror, a method for manufacturing an exposure mirror, and an exposure apparatus including the exposure mirror, which can detect states of the mirror such as damage and strain of the exposure mirror.

Background

In a proximity exposure apparatus, a mask having an exposure pattern formed thereon is disposed in proximity to a substrate to be exposed to light on which a photosensitive material is applied, with a gap of several 10 μm to several 100 μm, and the exposure pattern is transferred to the substrate to be exposed by irradiating exposure light from a light illumination device through the mask.

Patent document 1 proposes a proximity exposure method and a proximity exposure apparatus as follows: actuators capable of minute displacement are provided at a plurality of positions on the back surface of the optical path inverting mirror, and adjustment of parallelism of the exposure illumination light and correction of local expansion and contraction of the mask are performed by adjusting local curvature of the optical path inverting mirror.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 7-201711

Disclosure of Invention

Technical problem to be solved by the invention

However, since the optical path reversing mirror is made of glass, when the actuator attempts to change the local curvature of the optical path reversing mirror excessively, there is a possibility that damage such as a crack may occur in the optical path reversing mirror. In the exposure apparatus, since damage of the optical path reversing mirror affects the quality of a product to be exposed, it is necessary to immediately detect the damage of the optical path reversing mirror in the case of damage of the optical path reversing mirror in any chance.

As a method of detecting breakage of the mirror reflector, a method of detecting breakage from a broken acoustic waveform of glass by an acoustic wave, and a method of detecting breakage by detecting a vibration waveform at the time of breakage of glass directly from a glass surface can be considered. However, in the method of detecting a broken sound waveform or a vibration waveform at the time of breakage using glass, erroneous detection is often caused by the influence of the operation sound or vibration of the apparatus itself, and it is difficult to perform stable breakage detection. Further, the structure of the detector itself becomes complicated and expensive, and there is room for improvement.

The present invention has been made in view of the above-described problems, and an object thereof is to provide an exposure mirror capable of detecting a state of the mirror such as damage or strain with an inexpensive configuration, a method for manufacturing the exposure mirror, and an exposure apparatus including the exposure mirror.

Means for solving the problems

The above object of the present invention is achieved by the following configurations.

(1) An exposure mirror for reflecting light from a light source, the exposure mirror comprising:

a reflective film formed on a surface side of the plate glass and capable of reflecting light from the light source; and

and a conductive film formation pattern formed on the back surface side of the plate-shaped glass so as to be thinner than the reflective film and to be continuous from one end portion to the other end portion.

(2) The exposure mirror according to (1), wherein,

the film formation pattern is broken when the exposure mirror is damaged, and damage of the exposure mirror can be detected.

(3) The exposure mirror according to (1) or (2), wherein,

the film formation pattern is formed along an outer peripheral portion of the plate glass.

(4) The exposure mirror according to (1) or (2), wherein,

the film formation pattern is formed continuously from the one end portion to the other end portion through the outer peripheral portion and the inner portion of the plate glass.

(5) The exposure mirror according to (1) or (2),

the film formation pattern is formed by connecting a plurality of patterns having different resistance values in parallel from the one end portion to the other end portion.

(6) The exposure mirror according to (1) or (2),

when stress is applied to the film formation pattern, the resistance value of the film formation pattern changes, and the amount of strain of the exposure mirror can be detected.

(7) The exposure mirror according to any one of (1) to (6),

the reflective film and the film formation pattern are formed of the same metal material.

(8) A method for manufacturing an exposure mirror for reflecting light from a light source, the method comprising:

a step of shielding the periphery of a conductive film formation pattern that continues from one end portion to the other end portion on the back surface side of a plate-shaped glass; and

and depositing or sputtering a metal material from the front surface side of the plate glass to form a reflective film capable of reflecting light from the light source on the front surface side of the plate glass and to form the film formation pattern on the back surface side of the plate glass.

(9) An exposure device for a light source, which comprises a light source,

provided is an illumination device provided with: a light source; an integrator that uniformly emits light from the light source; and the exposure mirror of any one of (1) to (7), which reflects the light emitted from the integrator,

light from the illumination device is irradiated onto a workpiece through a mask, and an exposure pattern of the mask is exposed and transferred to the workpiece.

(10) The exposure apparatus according to (9),

the exposure mirror includes a mirror bending mechanism that is provided on a back surface side of the exposure mirror and is capable of changing a curvature of the exposure mirror.

Effects of the invention

According to the exposure mirror of the present invention, the state of the mirror, such as damage or strain amount of the exposure mirror, can be reliably detected with an inexpensive configuration by checking whether or not a film formation pattern formed on the back surface side of the plate glass is conductive.

Further, according to the method for manufacturing an exposure mirror of the present invention, the reflective film on the front surface side of the plate glass and the film formation pattern on the back surface side of the plate glass can be formed simultaneously by vapor deposition or sputtering of the metal material, and the exposure mirror capable of detecting the state of the mirror can be manufactured at low cost.

Further, according to the exposure apparatus of the present invention, the state of the mirror such as damage or strain amount of the exposure mirror can be reliably detected, and high-precision exposure can be maintained.

Drawings

Fig. 1 is a front view of a proximity exposure apparatus according to a first embodiment of the present invention.

Fig. 2 is a side view showing a configuration of a light irradiation apparatus applied to the proximity exposure apparatus shown in fig. 1.

Fig. 3(a) is a rear view of the exposure mirror shown in fig. 2, and (b) is a rear view showing a state in which the exposure mirror is broken.

Fig. 4(a) is a conceptual diagram illustrating a method of manufacturing an exposure mirror by sputtering, and (b) is a rear view thereof.

Fig. 5(a) is a rear view of the exposure mirror according to the second embodiment, and (b) is a rear view showing a state in which the exposure mirror is broken.

Fig. 6 is a rear view of the exposure mirror of the third embodiment.

Fig. 7(a) is a rear view of the exposure mirror according to the fourth embodiment, and (b) is a side view.

Description of the symbols

M mask

PE proximity exposure device

W workpiece

3 light irradiation device (Lighting device)

60 Lamp unit (light source)

65 integrator

70 mirror bending mechanism

100. 100A, 100B, 100C exposure mirror

101 plate glass

102 surface of

103 back side

104 reflective film

106. 106A, 106B, 106C film Forming Pattern

107 outer peripheral portion

108 one end part

109 the other end portion

113 inside

131 base material (Metal material)

Detailed Description

Hereinafter, an exposure mirror, a method for manufacturing an exposure mirror, and an exposure apparatus including the exposure mirror according to embodiments of the present invention will be described in detail with reference to the drawings.

(first embodiment)

As shown in fig. 1, the proximity exposure apparatus PE uses a mask M smaller than a workpiece W as an exposure target material, holds the mask M by a mask stage (mask supporting portion) 1, holds the workpiece W by a workpiece stage (workpiece supporting portion) 2, and irradiates light for pattern exposure from a proximity exposure apparatus light irradiation apparatus (hereinafter, also simply referred to as a light irradiation apparatus) 3 toward the mask M in a state where the mask M and the workpiece W are disposed in proximity to each other with a predetermined exposure gap, thereby transferring the pattern exposure of the mask M onto the workpiece W. Further, the workpiece stage 2 is moved in steps in two axial directions, i.e., the X-axis direction and the Y-axis direction, with respect to the mask M, and exposure transfer is performed for each step.

In order to step the workpiece stage 2 in the X-axis direction, an X-axis stage conveying mechanism 5 that steps an X-axis feed stage 5a in the X-axis direction is provided on the apparatus base 4. In order to step the workpiece stage 2 in the Y-axis direction, a Y-axis stage conveying mechanism 6 for stepping the Y-axis feed stage 6a in the Y-axis direction is provided on an X-axis feed stage 5a of the X-axis stage conveying mechanism 5. The workpiece stage 2 is provided on a Y-axis feed table 6a of the Y-axis stage conveying mechanism 6. The workpiece W is held on the upper surface of the workpiece stage 2 in a vacuum-sucked state by a workpiece chuck or the like. Further, a substrate-side displacement sensor 15 for measuring the height of the lower surface of the mask M is disposed on the side portion of the workpiece stage 2. Therefore, the substrate-side displacement sensor 15 can move in the X, Y-axis direction together with the workpiece stage 2.

A plurality of (4 in the illustrated embodiment) guide rails 51 of an X-axis linear guide are arranged in the X-axis direction on the apparatus base 4, and a slider 52 fixed to the lower surface of the X-axis feed table 5a is straddled on each guide rail 51. Thereby, the X-axis feed table 5a is driven by the first linear motor 20 of the X-axis stage conveying mechanism 5 and can reciprocate in the X-axis direction along the guide rail 51. Further, a plurality of guide rails 53 of the Y-axis linear guide are arranged in the Y-axis direction on the X-axis feed table 5a, and a slider 54 fixed to the lower surface of the Y-axis feed table 6a is straddled on each guide rail 53. Thereby, the Y-axis feed table 6a is driven by the second linear motor 21 of the Y-axis stage conveying mechanism 6 and can reciprocate in the Y-axis direction along the guide rail 53.

In order to move the workpiece stage 2 in the vertical direction, a vertical coarse adjustment device 7 and a vertical fine adjustment device 8 are provided between the Y-axis stage conveying mechanism 6 and the workpiece stage 2, the vertical coarse adjustment device 7 has a large positioning resolution but a large movement stroke and a large movement speed, and the vertical fine adjustment device 8 can perform positioning at a higher resolution than the vertical coarse adjustment device 7 and fine adjust the workpiece stage 2 vertically to finely adjust the gap between the facing surfaces of the mask M and the workpiece W to a predetermined amount.

The vertical rough adjustment device 7 moves the workpiece stage 2 up and down with respect to the fine adjustment stage 6b by an appropriate drive mechanism provided on the fine adjustment stage 6b described later. The stage coarse adjustment shafts 14 fixed to 4 positions on the bottom surface of the workpiece stage 2 are engaged with linear bearings 14a fixed to the fine adjustment stage 6b, and are guided in the vertical direction with respect to the fine adjustment stage 6 b. Further, the vertical rough adjustment device 7 is desired to have high repetitive positioning accuracy even if the resolution is low.

The vertical trimming device 8 includes a fixed table 9 fixed to the Y-axis feed table 6a and a guide rail 10 of a linear guide attached to the fixed table 9 in a state where an inner end side thereof is inclined obliquely downward, and a nut (not shown) of a ball screw is connected via a slider 11 straddling the guide rail 10 to a slider 12 reciprocating along the guide rail 10, and an upper end surface of the slider 12 is in slidable contact in a horizontal direction with respect to a flange 12a fixed to the trimming stage 6 b.

When the screw shaft of the ball screw is rotationally driven by the motor 17 attached to the fixed base 9, the nut, the slider 11, and the slider 12 move obliquely along the guide rail 10 as a unit, and the flange 12a is finely adjusted vertically.

In addition, the vertical trimming device 8 may drive the slider 12 by a linear motor instead of driving the slider 12 by the motor 17 and a ball screw.

The vertical trimming device 8 is provided with 1 on one end side (left end side in fig. 1) in the Y axis direction of the Z-axis feed table 6a, 2 on the other end side, and 3 in total, and is independently driven and controlled. Thus, the vertical fine adjustment device 8 independently finely adjusts the height of the flange 12a at 3 locations based on the measurement results of the amount of clearance between the mask M and the workpiece W measured at a plurality of locations by the clearance sensor 27, and finely adjusts the height and inclination of the workpiece stage 2.

In addition, when the height of the workpiece stage 2 can be sufficiently adjusted by the vertical fine adjustment device 8, the vertical coarse adjustment device 7 may be omitted.

Further, a bar mirror 19 facing the Y-axis laser interferometer 18 for detecting the position of the workpiece stage 2 in the Y-axis direction and a bar mirror (both not shown) facing the X-axis laser interferometer for detecting the position of the workpiece stage 2 in the X-axis direction are provided on the Y-axis feed table 6 a. The bar mirror 19 facing the Y-axis laser interferometer 18 is arranged along the X-axis direction on the side of the Y-axis feed stage 6a, and the bar mirror facing the X-axis laser interferometer is arranged along the Y-axis direction on the side of one end of the Y-axis feed stage 6 a.

The Y-axis laser interferometer 18 and the X-axis laser interferometer are always arranged to face the corresponding strip mirrors and supported by the apparatus base 4. In addition, the Y-axis laser interferometer 18 is provided with 2 stages separated in the X-axis direction. The Y-axis feed stage 6a and hence the position of the workpiece stage 2 in the Y-axis direction and the deflection error are detected by the 2Y-axis laser interferometers 18 via the bar mirrors 19. Further, the X-axis laser interferometer detects the position of the X-axis feed stage 5a and, hence, the workpiece stage 2 in the X-axis direction via the opposing strip mirrors.

The mask stage 1 includes: a mask base frame 24 formed of a substantially rectangular frame body; a mask frame 25 inserted into the central opening of the mask base frame 24 with a gap therebetween and supported movably in the directions X, Y and θ (in the plane X, Y); and a plurality of mask driving units 28 provided so as to be able to move the mask frame 25 in directions X, Y and θ with respect to the mask base frame 24, the mask base frame 24 being held at a fixed position above the workpiece stage 2 by a support column 4a provided so as to protrude from the apparatus base 4.

A frame-shaped mask holder 26 is provided on the lower surface of the central opening of the mask frame 25. That is, a plurality of mask holder suction grooves connected to a vacuum suction device, not shown, are provided on the lower surface of the mask frame 25, and the mask holder 26 is suction-held by the mask frame 25 via the plurality of mask holder suction grooves.

A plurality of mask suction grooves (not shown) for sucking the peripheral edge portion of the mask M, on which the mask pattern is not drawn, are opened in the lower surface of the mask holder 26, and the mask M is detachably held on the lower surface of the mask holder 26 by a vacuum suction device (not shown) via the mask suction grooves.

As shown in fig. 2, the light irradiation device 3 of the exposure apparatus PE of the present embodiment includes: a lamp unit 60 as a light source; a plane mirror 63 for changing the orientation of the optical path EL; an exposure control shutter unit 64 for controlling the opening and closing of the irradiation optical path; an integrator 65 disposed downstream of the exposure control shutter unit 64 and configured to uniformly emit light from the lamp unit 60; a plane mirror 66 disposed downstream of the integrator 65 and configured to change the direction of the optical path EL emitted from the integrator 65; a collimator mirror 67 for irradiating the light from the high-pressure mercury lamp 61 as parallel light; and a flat mirror 68 for irradiating the light from the collimator mirror 67 to the mask M.

The lamp unit 60 includes, for example, a plurality of high-pressure mercury lamps 61 and a reflector 62 for condensing light emitted from the high-pressure mercury lamps 61. The light source may be a single high-pressure mercury lamp 61 and reflector 62, or may be an LED.

The integrator 65 includes a plurality of lens elements, not shown, arranged in a matrix, and emits the light collected by the reflector 62 so as to have an illuminance distribution as uniform as possible in the irradiation region.

The plane mirror 63, the plane mirror 66, the collimator mirror 67, and the plane mirror 68 are mirrors that can reflect (substantially totally reflect) light of all wavelengths, and for example, aluminum films are formed on the reflection surfaces. The term "substantially total reflection" means a reflectance of 90% or more.

Further, a mirror bending mechanism 70 is disposed on the back surface side of the flat mirror 68. Thus, the planar mirror 68 can correct the off angle of the planar mirror 68 by changing the shape of the planar mirror 68 and locally changing the curvature of the reflection surface in response to a command from the mirror control unit 80 connected to each mirror bending mechanism 70 via the signal line 81.

In the light irradiation device 3, a polarization filter or a band-pass filter may be disposed between the integrator 65 and the exposure surface.

In the exposure apparatus PE configured as described above, in the light irradiation apparatus 3, if the exposure control shutter unit 64 is controlled to be opened during exposure, the light emitted from the high-pressure mercury lamp 61 is reflected by the plane mirror 63 and enters the entrance surface of the integrator 65. The light emitted from the exit surface of the integrator 65 is changed in its traveling direction by the plane mirror 66, the collimator mirror 67, and the plane mirror 68. This light is irradiated substantially perpendicularly as pattern exposure light to the mask M held on the mask stage 1, and further to the surface of the workpiece W held on the workpiece stage 2, so that the pattern of the mask M is exposed and transferred to the workpiece W.

Next, an exposure mirror (hereinafter, the plane mirror 63, the plane mirror 66, the collimator mirror 67, and the plane mirror 68 are collectively referred to as an exposure mirror 100)100 will be described.

As shown in fig. 3 a, a thin film of aluminum (not shown) having a thickness of several micrometers is formed on the exposure mirror 100 on the front surface 102 side of a rectangular plate-like glass 101 (the back surface side of the paper surface in fig. 3 a) by aluminum deposition or sputtering. The thin aluminum film is formed over the entire surface of the plate glass 101 on the front surface 102 side, and a reflective film 104 that totally reflects light from the light source 60 is formed.

On the back surface 103 side of the exposure mirror 100, a conductive film formation pattern 106 having a thickness of several micrometers is formed from a thin film of aluminum by vapor deposition or sputtering of aluminum. The film formation pattern 106 is formed continuously from one end 108 to the other end 109 along the outer peripheral portion 107 of the four sides of the plate glass 101 in a substantially square shape.

The film formation pattern 106 formed on the rear surface 103 side of the plate glass 101 is formed to be thinner than the reflection film 104 formed on the front surface 102 side. The reason for this will be described in the section of the method for manufacturing the exposure mirror 100.

Lead wires 110 and 111 are connected to one end 108 and the other end 109 of the film formation pattern 106, respectively. Further, by flowing a current between the pair of wires 110 and 111, damage to the exposure mirror 100 can be detected.

That is, when the exposure mirror 100 is not damaged by passing a current between the pair of lead wires 110 and 111 of the film formation pattern 106, the conduction between the pair of lead wires 110 and 111 can be detected by a galvanometer, not shown, and it can be confirmed that the exposure mirror 100 is in a normal state without being damaged.

On the other hand, as shown in fig. 3(b), when a crack 120 extending to the outer peripheral portion 107 is generated in the exposure mirror 100, the crack 120 breaks a part of the film formation pattern 106, and the current flow between the pair of wires 110 and 111 is interrupted. Therefore, by detecting the interruption of the current between the pair of lead wires 110 and 111, damage to the exposure mirror 100 can be detected immediately and reliably.

Since the film formation pattern 106 is formed of a thin film having a thickness of several micrometers thinner than the reflective film 104, the exposure mirror 100 is not broken and is not in a state of only thin film connection. Therefore, the occurrence of the crack 120 can reliably detect the damage of the exposure mirror 100.

Further, since the film formation pattern 106 has a minute resistance, it can be confirmed that the exposure mirror 100 has no damage by measuring the resistance value between the pair of lead wires 110 and 111 using a resistance meter or the like instead of measuring the current value by flowing the current between the pair of lead wires 110 and 111.

Next, a method for manufacturing the exposure mirror 100 will be described with reference to fig. 4(a) and (b).

The exposure mirror 100 is formed by depositing or sputtering aluminum as a metal material from the front surface 102 side of the plate-shaped glass 101 to form a reflective film 104 on the front surface 102 side of the plate-shaped glass 101 and simultaneously form a film formation pattern 106 on the back surface 103 side of the plate-shaped glass 101.

Specifically, as shown in fig. 4(b), on the rear surface 103 side of the plate glass 101, a portion other than the film formation pattern 106 that continues from the one end 108 to the other end 109 along the outer peripheral portion 107 of the plate glass 101 is shielded by the shield 130. Then, aluminum as the base material 131 is disposed on the front surface 102 side of the plate glass 101, and the aluminum is deposited or sputtered to form the reflective film 104 on the front surface 102 side of the plate glass 101 and the film formation pattern 106 on the back surface 103 side of the plate glass 101. Then, after film formation, the shield 130 is removed from the back surface 103 of the plate glass 101.

The vapor deposition is a method of forming a film of decomposed aluminum molecules on the plate glass 101 by applying electron beams and heat to the base material (aluminum in the present embodiment) 131 in vacuum, and the sputtering is a method of forming a film of aluminum molecules flying out from the base material 131 by ionizing Ar gas filled in the chamber by electricity and causing them to collide with the base material 131 on the plate glass 101. In fig. 4(a), reference numeral 132 denotes an arrow indicating the direction in which aluminum molecules move.

When aluminum molecules are formed on the plate glass 101, the aluminum molecules also go around from the front surface 102 to the back surface 103 of the plate glass 101 where the base material (aluminum) 131 faces, and a thin film of aluminum is also formed on the back surface 103. The thickness of the thin film after film formation tends to be as follows: the thin film formed on the front surface 102 of the plate glass 101 near the base material 131 is thicker than the thin film formed on the back surface 103 around the plate glass 101.

In the exposure mirror 100 of the present embodiment, a mask 130 having a desired pattern is provided in advance on the rear surface 103 of the plate glass 101, aluminum is formed by vapor deposition or sputtering from the front surface 102, the reflective film 104 is formed on the front surface 102, and the film formation pattern 106 is formed by a thin film formed on the rear surface 103 by utilizing a wraparound phenomenon of aluminum molecules to the rear surface 103.

Thus, the conductive thin film pattern as the film formation pattern 106 can be formed at a very low cost without performing a special process other than masking the rear surface 103.

In addition, when the mirror bending mechanism 70 is disposed on the rear surface 103 of the exposure mirror 100, as in the flat mirror 68 shown in fig. 2, the position where the mirror bending mechanism 70 is disposed does not need to be away from the film formation pattern 106, and can be attached to the film formation pattern 106 without hindrance. Therefore, the arrangement position of the mirror bending mechanism 70 is not restricted by the film formation pattern 106. Further, it is more preferable to form a protective film on the film formation pattern 106 and to dispose the mirror bending mechanism 70 on the protective film.

In the above description, the reflective film 104 on the front surface 102 and the film formation pattern 106 on the back surface 103 of the exposure mirror 100 are simultaneously formed using the same base material 131, but the reflective film 104 and the film formation pattern 106 may be formed in different steps using different metals.

For example, as an example of the metal used for the reflective film 104 on the surface 102, silver may be mentioned in addition to the above aluminum. However, in an exposure apparatus using ultraviolet light as a light source such as a proximity exposure apparatus, aluminum is preferable because aluminum has a high reflectance in the ultraviolet region. In addition, as the surface 102, a dielectric mirror can be used in addition to a metal mirror.

Examples of the metal used for the film formation pattern 106 on the rear surface 103 include silver, copper, and the like, in addition to the aluminum. However, aluminum is preferred in terms of ease of film formation, low cost, and the like. In any case, the film formation pattern 106 on the back surface 103 is formed thinner than the reflective film 104 on the front surface 102.

As described above, the exposure mirror according to the present embodiment includes: a reflective film formed on a surface side of the plate glass and capable of reflecting light from the light source; and a conductive film formation pattern which is formed on the back surface side of the plate glass so as to be thinner than the reflective film and to be continuous from one end portion to the other end portion, wherein the conductive film formation pattern is broken when the exposure mirror is damaged, and damage of the exposure mirror can be detected. Thus, whether or not the film formation pattern is on can be checked, and the presence or absence of damage to the exposure mirror can be reliably detected.

Further, since the film formation pattern is formed along the outer peripheral portion of the plate glass, damage occurring in the outer peripheral portion of the exposure mirror can be detected.

Further, since the reflective film and the film formation pattern are formed of the same metal material, the reflective film and the film formation pattern can be formed simultaneously, and the exposure mirror can be manufactured at low cost.

Further, the method for manufacturing an exposure mirror according to the present embodiment includes: a step of shielding the periphery of a conductive film formation pattern which is continuous from one end portion to the other end portion on the back side of a plate-shaped glass, is broken when an exposure mirror is damaged, and can detect damage of the exposure mirror; and depositing or sputtering a metal material from the front surface side of the plate-shaped glass to form a reflective film capable of reflecting light from the light source on the front surface side of the plate-shaped glass and to form a film formation pattern on the back surface side of the plate-shaped glass. Thus, the reflective film on the front surface side of the plate glass and the film formation pattern on the back surface side of the plate glass can be simultaneously formed without performing any special treatment other than masking the back surface of the plate glass, and the exposure mirror capable of detecting the state of the mirror can be manufactured at low cost.

Further, an exposure apparatus according to the present embodiment includes an illumination apparatus including: a light source; an integrator that uniformly emits light from the light source; and an exposure mirror that reflects light emitted from the integrator, irradiates a workpiece with light from the illumination device via a mask, and exposes and transfers an exposure pattern of the mask to the workpiece, so that damage to the exposure mirror can be reliably detected, and high-precision exposure can be maintained.

Further, since the exposure mirror includes the mirror bending mechanism provided on the back surface side thereof and capable of changing the curvature of the exposure mirror, the curvature of a part of the exposure mirror can be changed, and adjustment of the parallelism of the exposure illumination light and correction of local expansion and contraction of the mask can be performed. In particular, the exposure mirror can more reliably detect the breakage of the mirror due to curvature correction using the film formation pattern.

(second embodiment)

Fig. 5(a) is a rear view of an exposure mirror according to the second embodiment, and fig. 5(b) is a rear view of an exposure mirror partially broken.

As shown in fig. 5(a), in the exposure mirror 100A of the present embodiment, a film formation pattern 106 formed of an aluminum thin film is continuously formed on the back surface 103 of the exposure mirror 100A from one end 108 to the other end 109 via an outer peripheral portion 107 of a plate-shaped glass 101 and an inner portion 113 inside the outer peripheral portion 107. Specifically, the molding pattern 106 is formed in a substantially square shape along the outer peripheral portion 107 of the plate glass 101, and is formed in a substantially zigzag shape so as to pass through substantially the entire surface of the inner portion 113 which is the inner side of the outer peripheral portion 107.

Lead wires 110 and 111 are connected to one end 108 and the other end 109 of the film formation pattern 106, respectively. Thus, by passing a current between the pair of wires 110 and 111, the presence or absence of damage to the exposure mirror 100 can be detected.

As shown in fig. 5(b), according to the exposure mirror 100A of the present embodiment, the film formation pattern 106 formed of a thin film of aluminum passes through the outer peripheral portion 107 of the back surface 103 and the inner portion 113, and the inner portion 113 is formed in a substantially zigzag shape. Therefore, even if the damage of the exposure mirror 100A does not extend to the outer peripheral portion 107 but stays in the local crack 120 of the inner portion 113, or even if the damage of the exposure mirror 100A does not extend to the inner portion 113 but stays in the local crack 120 of the outer peripheral portion 107, the film formation pattern 106 is cut at a position where the crack 120 passes through the film formation pattern 106, and the pair of lead wires 110 and 111 are not electrically connected. Thus, even if damage to the exposure mirror 100A is a local crack 120, it can be immediately and reliably detected.

The film formation pattern 106 formed in the interior 113 is not limited to a substantially zigzag shape, and may have any shape as long as it is a pattern formed by vapor deposition or sputtering, such as a spiral pattern.

(third embodiment)

Fig. 6 is a rear view of the exposure mirror of the third embodiment. As shown in fig. 6, an exposure mirror 100B according to the third embodiment includes: a first film formation pattern 106A formed of a thin film formed on the outer peripheral portion 107 of the plate glass 101, and a second film formation pattern 106B formed of a thin film formed on the inner portion 113 of the plate glass 101. The first and second film formation patterns 106A and 106B have resistance values set to be different from each other.

One ends 108a, 108B of the first film-formed pattern 106A and the second film-formed pattern 106B are joined to each other at one end portion 108, the other ends 109a, 109B are joined to each other at the other end portion 109, and lead wires 110, 111 are connected to the one end portion 108 and the other end portion 109, respectively. That is, the first film formation pattern 106A and the second film formation pattern 106B are connected in parallel.

Therefore, if the resistance values of the first and second film formation patterns 106A and 106B are measured in advance, when at least one of the first and second film formation patterns 106A and 106B is broken, by detecting the resistance value between the lead wires 110 and 111, it is possible to recognize which of the first and second film formation patterns 106A and 106B is broken. That is, whether the damage of the exposure mirror 100B is generated in the outer peripheral portion 107 or the inner portion 113 of the plate glass 101 can be determined, and the approximate damage position can be known.

When the resistance value between the conductive wires 110 and 111 becomes an insulation level, it can be detected that both the film formation patterns 106A and 106B are broken, that is, that the exposure mirror 100B is largely damaged.

(fourth embodiment)

Fig. 7(a) is a rear view of an exposure mirror according to the fourth embodiment, and fig. 7(b) is a side view. As shown in fig. 7(a) and (b), the exposure mirror 100C according to the fourth embodiment has a film formation pattern 106C formed on the back surface 103 thereof in the same shape as the strain gauge (i.e., in a shape defined by the grid length, the grid width, and the number of grids).

That is, when the exposure mirror 100C is bent and a stress acts on the film formation pattern 106C, the film formation pattern 106C is continuously formed by a thin film made of a material whose resistance value changes, and the leads 110 and 111 are connected to one end portion 108 and the other end portion 109, respectively.

Therefore, the amount of strain of the exposure mirror 100C can be known from a slight change in resistance between the wires 110 and 111. When the resistance value between the wires 110 and 111 indicates the insulator level, it is determined that the film formation pattern 106C is cut, that is, the exposure mirror 100C is damaged. This makes it possible to detect not only damage occurring in the exposure mirror 100C but also the amount of strain of the exposure mirror 100C.

In particular, in the present embodiment, the curvature of the plane mirror 68 can be detected by forming the film formation pattern 106C for detecting the strain amount in the present embodiment on the plane mirror 68 provided with the mirror bending mechanism 70.

Further, the local curvature of the plane mirror 68 provided with the mirror bending mechanism 70 may be detected by forming a plurality of film formation patterns 106C having different resistance values for each region in a shape capable of measuring the amount of strain, and connecting the plurality of film formation patterns 106C in parallel.

When the material for forming the reflective film 104 on the front surface 102 side of the exposure mirror 100C is different from the material for forming the film formation pattern 106C on the rear surface 103 side, which can detect the amount of strain, the reflective film 104 and the film formation pattern 106C may be formed by different processes.

The present invention is not limited to the above embodiments, and modifications, improvements, and the like can be appropriately made.

In addition, the present application is based on the japanese patent application (japanese patent application 2019-.