JP2005300770A - Microscopic device and exposure apparatus provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microscopic device reducing the influence of heat of illumination light on a microscope body part and having high detection accuracy and an exposure apparatus provided with the microscopic device. <P>SOLUTION: The microscopic device 38 is provided with a microscope body part 80 having an introduction hole 78 for introducing illumination light and a light shielding stop 96 arranged on the front stage of the introduction hole 78 of the microscope body part 80 to shield a part of illumination light introduced from the introduction hole 78 into the microscope body part 80. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a microscope apparatus and an exposure apparatus including the same.

Light from the light source lamp is introduced into the main body of the microscope through the projection tube, and the introduced illumination light is emitted from the objective lens of the observation optical system through the illumination optical system, and reflected light from the observation object is transmitted through the observation optical system. As a microscope apparatus to be detected, there is one disclosed in Patent Document 1, for example.
JP 2002-98905 A

  However, in the above-described microscope apparatus, the temperature of the microscope body may rise due to the heat of the illumination light introduced into the microscope body, causing thermal expansion. As a result, the focal position of the objective lens attached to the tip of the microscope main body may shift. As a result, when the microscope apparatus having such a structure is used, for example, for alignment between a mask and a wafer of an exposure apparatus, there is a problem that alignment detection is not stable and an alignment error occurs.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a microscope apparatus with high detection accuracy in which the influence of the heat of illumination light on the microscope main body is reduced, and an exposure apparatus including the same. And

  The microscope apparatus according to the present invention is provided with a microscope main body having an introduction hole for introducing illumination light, and an illumination light introduced into the microscope main body from the introduction hole. And a light-shielding stop for shielding a part of the light-shielding aperture.

  In this microscope apparatus, since a light-shielding stop is provided in front of the introduction hole of the microscope main body, unnecessary light introduced into the microscope main body (refers to a light beam other than the light beam that forms an image on the imaging device) is reduced. be able to. As a result, thermal expansion of the microscope main body is suppressed, and detection accuracy is improved.

  The microscope apparatus according to the present invention may be provided with a lens that is provided in front of the light-shielding diaphragm and that makes illumination light substantially parallel. In this way, since light that is substantially parallel is incident on the light-shielding diaphragm, it is not necessary to strictly position the light-shielding diaphragm, and positioning of the light-shielding diaphragm becomes easy.

  The microscope apparatus according to the present invention may include a light projecting tube that holds a light-shielding diaphragm and a lens, and the light projecting tube and the microscope main body may be connected via a heat insulating member. By providing the light projecting tube in this way, positioning between the light-shielding diaphragm and the lens becomes easy. In addition, since the light projecting tube and the microscope main body are connected via a heat insulating member, heat conduction from the light projecting tube to the microscope main body is suppressed, and detection accuracy is further improved.

  The microscope apparatus according to the present invention may include a heat transfer member for releasing heat accumulated in the light projecting tube. In this way, the heat conduction from the light projecting tube to the microscope main body is further suppressed, and the influence of the illumination light on the microscope main body can be further reduced, so that the detection accuracy can be further improved.

  In the microscope apparatus according to the present invention, the microscope body may include a field stop, and the opening diameter of the light-shielding stop may be larger than the opening diameter of the field stop. In this way, there is no inconvenience that a portion where the illumination light does not strike is generated inside the field stop, and the detection accuracy can be further improved.

  An exposure apparatus according to the present invention includes a vacuum chamber, any one of the above-described microscope apparatuses provided in the vacuum chamber, a light source lamp provided outside the vacuum chamber for supplying illumination light to the microscope apparatus, and a light source lamp A light guide for guiding the illumination light from the microscope apparatus to the microscope apparatus, a substrate holding part for positioning and holding the substrate in the vacuum chamber, and a mask for positioning and holding the desired pattern formed in the vacuum chamber And a light source for exposure for transferring a desired pattern onto the substrate through the mask.

  Since this exposure apparatus includes the above-described microscope apparatus, the alignment accuracy between the mask and the substrate is increased, and ideal alignment exposure processing is possible.

  ADVANTAGE OF THE INVENTION According to this invention, the microscope apparatus with high detection accuracy which reduced the influence which the heat | fever of illumination light exerts on a microscope main-body part, and an exposure apparatus provided with the same are provided.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a perspective view showing the arrangement of an exposure apparatus according to this embodiment. FIG. 2 is a partial sectional view for explaining the configuration of the exposure apparatus shown in FIG. As shown in FIGS. 1 and 2, the exposure apparatus 10 includes a vacuum chamber 12.

  The vacuum chamber 12 includes a container body 14 having an upper end opened, and an upper lid 16 that closes the upper opening of the container body 14.

  The upper lid 16 has a rectangular rectangular cross section, and an electron beam irradiation unit (exposure light source) 18 for irradiating an electron beam at the center is provided. As shown in FIG. 2, the electron beam irradiation unit 18 includes an electron lens barrel 20 including an upper wall portion and a side wall portion, an electron gun 22 provided on the upper wall portion in the electron lens barrel 20, and an electron gun 22. A lens 24 for collimating the electron beam emitted from the light source and a polarizer 26 are provided. The electron gun 22, the lens 24, and the polarizer 26 are arranged in this order downward in the vertical direction. The electron beam emitted from the electron gun 22 is collimated by the lens 24 and scanned by the polarizer 26. The semiconductor wafer W (substrate) is irradiated through the mask M.

  As shown in FIGS. 1 and 2, the container main body 14 has a bottom wall portion 14a having a rectangular cross section and two sets of side wall portions 14b erected on the edge of the bottom wall portion 14a. A wafer stage (substrate holding unit) 28 for positioning and holding the semiconductor wafer W for performing the exposure process is accommodated in the container body 14. The wafer stage 28 includes a positioning stage 30 that positions the semiconductor wafer W, and an electrostatic chuck 32 that is mounted on the positioning stage 30 and holds the semiconductor wafer W by suction. The positioning stage 30 is a coarse movement stage that performs rough positioning in two axial directions (XY directions) orthogonal to each other in a horizontal plane, and is mounted on the coarse movement stage, and the vertical direction (Z direction) perpendicular to the XY direction and the XY direction. , A rotation direction (θ direction) in the horizontal plane, and a fine movement stage that finely adjusts the inclination. The electrostatic chuck 32 is mounted on this fine movement stage. Therefore, the semiconductor wafer W is positioned by the positioning stage 30 while being attracted by the electrostatic chuck 32.

  Further, as shown in FIG. 2, a mask stage (mask holding part) 34 for positioning and holding a mask M on which a desired pattern is formed is accommodated in the container main body 14. The mask stage 34 performs positioning in a rotational direction (θ direction), a vertical direction (Z direction), and a fine tilt in a horizontal plane. The mask stage 34 is mounted on a reference base 36 fixed in the vacuum chamber 12.

  In the container body 16, a microscope device 38 for alignment between the mask M and the wafer W is provided. As shown in FIG. 3, the microscope apparatus 38 includes a microscope main body 80 and a light introducing portion 81.

  The microscope main body 80 includes a plurality of optical elements 82 to 90 and an imaging device 92. The plurality of optical elements 82 to 90 are built in a housing 93 formed of a metal material such as aluminum. An introduction hole 78 for introducing illumination light is provided in the upper wall portion of the housing 93. A reflection mirror 82 that reflects illumination light introduced through the introduction hole 78 is provided in the housing 93 immediately below the introduction hole 78. A field stop 83 is provided on the optical path of the illumination light reflected by the reflecting mirror 82 and having its optical path bent 90 degrees. The field stop 83 limits the range of illumination light on the object. A prism 85 and a lens 86 are provided on the optical path of the illumination light that has passed through the field stop 83. A half mirror 87 is provided on the optical path of the illumination light that has been bent 90 degrees by the prism 85 and passed through the lens 86. The half mirror 87 reflects the illumination light and transmits the reflected light from the object. A first objective lens 88 is provided on the optical path of the illumination light reflected by the half mirror 87 and bent by 90 degrees. Illumination light emitted through the first objective lens 88 is applied to an object such as the mask M or the semiconductor wafer W.

  A second objective lens 90 for image formation is provided on the optical path of the detection light incident through the first objective lens 88 and transmitted through the half mirror 87. An imaging device 92 is provided on the optical path of the detection light transmitted through the second objective lens 90. Note that a CCD camera can be used as the imaging device 92.

  As shown in FIGS. 3 and 4, the light introducing portion 81 includes a cylindrical light projecting tube 94, a condenser lens 95 positioned and fixed in the light projecting tube 94, and a light blocking diaphragm 96. Yes. The light projection tube 94 is made of a metal material such as aluminum. At the upper end portion of the light projecting tube 94, the inner diameter is smaller than the other parts, and an emission end 61a of a light guide 61 (to be described later) can be inserted and fixed. The condenser lens 95 makes the light emitted from the light emitting end 61a of the light guide 61 and having a broadened shape substantially parallel. The light-shielding diaphragm 96 has a function of shielding extra light that does not contribute to detection out of illumination light introduced into the microscope main body 80, and does not participate in the imaging of the mask M and the semiconductor wafer W at all. That is, in the observation optical system to be described later of the microscope main body 80, there is no image that is in a conjugate relationship (related to image formation) with the light-shielding stop 90. Therefore, even if the light-shielding diaphragm 96 is inserted, the brightness and sharpness of the image do not change, and the light-shielding diaphragm 96 has a completely different function from a field diaphragm or an aperture diaphragm that is generally used.

  In the microscope apparatus 38 according to this embodiment described above, the condenser lens 95, the light-shielding diaphragm 96, the reflection mirror 82, the field diaphragm 83, the prism 85, and the lens 86 constitute an illumination optical system for Keller illumination. The first objective lens 88, the half mirror 87, and the second objective lens 90 constitute an observation optical system.

  Here, the aperture diameter of the light-shielding diaphragm 96 is preferably larger than the aperture diameter of the field diaphragm 83 described above. By doing so, there is no inconvenience that a portion where the illumination light does not strike is generated inside the field stop 83 projected on the mask M surface and the semiconductor wafer W surface.

  The condenser lens 95 is preferably provided in front of the light-shielding diaphragm 96. In this way, illumination light that is substantially parallel is incident on the light-shielding diaphragm 96, so that it is not necessary to strictly position the light-shielding diaphragm 96, and positioning of the light-shielding diaphragm 96 is facilitated.

  In addition, an outward flange is provided at the lower end portion of the light projecting tube 94 so that it can be screwed in the vicinity of the introduction hole 78 in the upper wall portion of the microscope main body 80.

  Here, in this microscope apparatus 38, heat is stored in the light projecting tube 94 in order to block extra light for detection by the light blocking diaphragm 96. In order to suppress heat conduction to the microscope main body 80 of the heat stored in the light projecting tube 94, the following configuration is provided.

  That is, the light projection tube 94 and the microscope main body 80 are connected via the annular heat insulating member 97 as shown in FIGS. The heat insulating member 97 is made of a material having low thermal conductivity such as ceramic. The light projecting tube 94 is provided with a heat transfer member 98 for releasing heat accumulated in the light projecting tube 94. The heat transfer member 98 includes an annular fixed portion 71 attached to the outer peripheral surface of the light projecting tube 94 and a tropical zone 72 extending from the fixed portion 71. The fixing portion 71 and the tropical zone 72 are made of a material having high thermal conductivity, such as copper. As shown in FIG. 2, the front end of the tropical zone 72 is connected to the reference base 36. The reference base 36 is cooled by a cooling device (not shown), and heat exchange is performed here, whereby heat radiation from the light projecting tube 94 is promoted.

  The microscope device 38 is mounted on the reference base 36. The alignment image detected by the microscope apparatus 38 is sent to an image processing apparatus (not shown) for processing, and the positional relationship between the mask M and the semiconductor wafer W is obtained from the degree of alignment mark alignment. When the mask M and the semiconductor wafer W are misaligned, a signal for correcting the position of the mask M and / or the semiconductor wafer W is generated. Based on this signal, the position of the mask M and / or the semiconductor wafer W is determined. Minor correction. In this way, precise positioning between the mask M and the semiconductor wafer W is performed. In the present embodiment, the mask M is arranged close to the semiconductor wafer W (the gap between the mask M and the semiconductor wafer W is about 50 μm).

  The internal space of the vacuum chamber 12 is decompressed by a vacuum pump (not shown). Under this reduced pressure environment, the entire surface of the mask M is scanned with the electron beam emitted from the electron beam irradiation unit 18, whereby the desired pattern is transferred to the resist on the semiconductor wafer W at the same magnification.

  As shown in FIGS. 1 and 2, the vacuum chamber 12 is mounted on a vibration isolation table 40 provided below the bottom wall portion 14a. A power supply device 42 for generating a DC voltage from the AC voltage is installed in a space between the installation surface of the vacuum chamber 12 and the bottom wall portion 14a.

  Further, as shown in FIGS. 1 and 2, the exposure apparatus 10 includes a frame 46 for supporting a light source lamp 44 described later. The frame 46 includes four vertical frames 48 extending in the vertical direction, and four upper frames 50 that are horizontally mounted on the upper ends of the four vertical frames 48. A plurality of connecting ribs (not shown) are laid across the upper frame 50. The frame body 46 is disposed so as to surround the vacuum chamber 12.

  The exposure apparatus 10 includes four light source lamps 44 as shown in FIGS. Each light source lamp 44 has a rectangular parallelepiped shape. The light source lamp 44 has an Xe lamp (not shown) housed in a housing. A light guide 60 for guiding the light emitted from the Xe lamp is drawn out from the front wall portion of the light source lamp 44, and a power cable 62 for feeding is drawn out from the rear wall portion. Further, an exhaust heat line 64 for releasing heat generated in the housing portion 56 is drawn out from the rear wall portion of the light source lamp 44.

  The light source lamp 44 having such a configuration is suspended and supported by four upper frames 50 (including connection ribs between the upper frames 50 (not shown)) of the frame body 46. The four light guides 60 drawn from the front wall portions of the light source lamps 44 are introduced into the four side wall portions 14b of the vacuum chamber 12, and are optically coupled to the light guides 61 inside the vacuum chamber 12 here. Has been. A light guide 61 inside the vacuum chamber 12 is introduced into the microscope apparatus 38. Further, the four power supply cables 62 drawn out from the rear wall portions of the light source lamps 44 are respectively connected to the power supply device 42 installed below the vacuum chamber 12 through the vertical frame 48.

  Further, as shown in FIGS. 1 and 2, the exposure apparatus 10 includes an exhaust heat duct 70 for exhausting heat generated from the light source lamp 44. The exhaust heat duct 70 is supported by being suspended on the upper frame 50 of the frame 46 above the vacuum chamber 12. A heat exhaust line 64 drawn from the rear wall of each light source lamp 44 is connected to the heat exhaust duct 70.

  Next, operations and effects of the exposure apparatus 10 according to the present embodiment will be described.

  In transferring the desired pattern onto the resist on the semiconductor wafer W, first, the semiconductor wafer W is supplied into the vacuum chamber 12 and is attracted onto the electrostatic chuck 32, and provisional positioning is performed by the positioning stage 30. Further, a mask M having a desired pattern is supplied into the vacuum chamber 12, and provisional positioning is performed by the mask stage 34. In this state, a DC voltage is supplied from the power supply device 42 to the light source lamp 44 through the power cable 62, and light emitted from the Xe lamp is supplied into the vacuum chamber 12 through the light guide 60. The light emitted from the distal end portion of the light guide 60 is incident on the light guide 61 in the vacuum chamber 12, propagates, and is sent to the microscope apparatus 38.

  The illumination light that has passed through the light guide 61 in the vacuum chamber 12 and is emitted from the emission end 61a into the light projection tube 94 at a predetermined spread angle is converted into substantially parallel light by the condenser lens 95, as shown in FIG. The Next, extra light for detection is blocked by the light blocking diaphragm 96. At this time, the shielded light is changed into heat in the light projecting tube 94, but a heat insulating member 97 is provided between the light projecting tube 94 and the microscope main body 80. Further, heat radiation from the light projecting tube 94 is promoted by the heat transfer member 98. As a result, heat conduction to the microscope body 80 is suppressed.

  The light transmitted through the light blocking diaphragm 96 is introduced into the microscope main body 80 through the introduction hole 78. The illumination light introduced into the microscope main body 80 is reflected by the reflection mirror 82 and the optical path is bent by 90 degrees, and then enters the field stop 83. Illumination light stopped at the field stop 83 is incident on the half mirror 87 through the prism 85 and the lens 86. The illumination light reflected by the half mirror 87 is emitted from the microscope main body 80 through the first objective lens 88.

  The illumination light emitted from the microscope apparatus 38 is irradiated from an oblique direction to alignment marks (not shown) on the mask M and the semiconductor wafer W. Then, the edge scattered light reflected by the alignment mark enters the microscope main body 80 through the first objective lens 88 and is detected by the imaging device 92 through the second objective lens 90. The alignment image detected by the microscope apparatus 38 is sent to an image processing apparatus (not shown) and processed, and the positional relationship between the mask M and the semiconductor wafer W is obtained from the degree of alignment mark alignment. Note that such position detection by the oblique detection method using edge scattered light is disclosed in, for example, Japanese Patent Application Laid-Open No. 10-242036, and detailed description thereof is omitted.

  When the mask M and the semiconductor wafer W are misaligned, a signal for correcting the position of the mask M and / or the semiconductor wafer W is generated, and the mask stage 34 and / or the wafer stage 28 is driven based on this signal. Thus, the position of the mask M and / or the semiconductor wafer W is finely corrected. As a result, the mask M and the semiconductor wafer W are accurately positioned in the proximity of each other.

  After positioning the mask M and the semiconductor wafer W, irradiation of the electron beam from the electron beam irradiation unit 18 is started. The electron beam emitted from the electron gun 22 of the electron beam irradiation unit 18 is collimated by the lens 24 and scanned by the polarizer 26 to scan the entire surface of the mask M. Thereby, a desired mask pattern is transferred to the resist on the semiconductor wafer W at the same magnification.

  As described above, in the present embodiment, since the light blocking diaphragm 96 is provided in front of the introduction hole 78 of the microscope main body 80, light unnecessary for detection introduced into the microscope main body 80 can be reduced. Therefore, the thermal expansion of the microscope body 80 is suppressed, and the detection accuracy can be improved. This configuration is extremely effective when it is not desired to reduce the luminance but it is not desired to introduce light unnecessary for detection into the microscope main body 80.

  Here, the numerical aperture NA of the light guide 61 is 0.39, and the spread angle is 23 degrees. The effective diameter of the floodlight tube 94 is 16 mm, and the take-in angle is 15 degrees. At this time, when the light blocking diaphragm 96 is not provided, about 60% of the illumination light emitted from the emission end 61a of the light guide 61 hits the inner wall of the light projection tube 94 and becomes heat, while the remaining about 40% is introduced. It is introduced into the microscope main body 80 from the hole 78. Due to the introduced 40% illumination light, the microscope main body 80 is thermally expanded, the focal position of the first objective lens 88 is displaced, alignment detection is not stable, and an alignment error is caused.

  On the other hand, since the light-shielding diaphragm 96 is provided in the microscope apparatus 38, when the aperture diameter of the light-shielding diaphragm 96 is 4 mm (the aperture diameter of the light-shielding diaphragm 96 is defined in consideration of the aperture diameter of the field diaphragm 83). In this case, since the aperture diameter of the field stop 83 is 1.7 mm, it is a value with a margin of about twice that size.), About 97.5% of light is shielded and the rest Only about 2.5% of the illumination light is introduced into the microscope main body 80 from the introduction hole 78. Thus, according to the microscope apparatus 38, the amount of illumination light unnecessary for detection introduced into the microscope main body 80 can be reduced from 40% to 2.5%.

  Here, although the illumination light unnecessary for the detection introduced into the microscope main body 80 is reduced, the light shielded by the light shielding diaphragm 96 is converted into heat in the light projection tube 94. When this heat is conducted to the microscope main body 80, the microscope main body 80 may be thermally expanded to shift the focal position. In order to prevent this heat conduction, the light projection tube 94 and the microscope main body 80 are connected via a heat insulating member 97. As a result, the thermal expansion of the microscope body 80 is suppressed, and the accuracy of position detection can be improved.

  In this embodiment, since the heat transfer member 98 for releasing the heat accumulated in the light projecting tube 94 is provided, heat conduction from the light projecting tube 94 to the microscope main body 80 is further suppressed. The radiation from the microscope apparatus 80 is reduced. As a result, the expansion of the mask M and the temperature rise of the peripheral members are suppressed, and it is possible to further improve the accuracy of position detection.

  In this embodiment, since the condenser lens 95 is provided in front of the light-shielding diaphragm 96, light that is made substantially parallel is incident on the light-shielding diaphragm 96, and the light-shielding diaphragm 96 is positioned accurately. Therefore, it is easy to position the light-shielding diaphragm 96 in the optical axis direction.

  Further, since the aperture diameter of the light-shielding diaphragm 96 is larger than the aperture diameter of the field diaphragm 83, a portion where the illumination light does not strike is generated inside the field diaphragm 83 projected on the mask M surface and the semiconductor wafer W surface. There is no inconvenience.

  Thereby, in the exposure apparatus 10 provided with such a microscope apparatus 38, the alignment accuracy between the mask M and the semiconductor wafer W is increased, and an ideal alignment exposure process is possible.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, as shown in FIG. 5, the condenser lens 95 may be fixed by a stepped portion 79 of the light projecting tube 94 and a light-shielding diaphragm 96 screwed into the light projecting tube 94. In this way, the light-shielding diaphragm 96 also serves as a holding ring for the condenser lens 95.

  In the above-described embodiment, glass fibers, plastic fibers, liquid fibers, or the like may be used as the light guides 60 and 61.

  In the above-described embodiment, the oblique detection method using edge scattered light is described as the alignment detection method, but the detection method is not particularly limited, and other methods such as a vertical detection method may be used.

  The present invention is also applicable to an exposure process for patterning a predetermined film on a glass substrate in forming a liquid crystal panel.

  Further, the microscope apparatus according to the present invention is not limited to the exposure process using an electron beam, but can be applied to other exposure processes.

  Furthermore, the microscope apparatus according to the present invention can be applied to an apparatus that requires positioning in substrate processing under a vacuum atmosphere in addition to exposure processing.

It is a figure which shows the structure of the electron beam exposure apparatus which concerns on this embodiment. It is sectional drawing which shows the structure of the electron beam exposure apparatus of FIG. It is a figure which shows the structure of a microscope apparatus. It is a disassembled perspective view which shows the structure of a microscope apparatus. It is sectional drawing which shows the modification of the light introduction part which has a light projection tube, a condenser lens, and a light-shielding stop.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Electron beam exposure apparatus, 12 ... Vacuum chamber, 18 ... Electron beam irradiation part, 28 ... Wafer stage, 34 ... Mask stage, 44 ... Light source lamp, 60, 61 ... Light guide, 78 ... Introduction hole, 80 ... Microscope main body 83: Field stop, 94: Projection tube, 95: Condenser lens, 96: Light blocking stop, 97: Heat insulation member, 98: Heat transfer member

Claims (6)

A microscope body having an introduction hole for introducing illumination light;
A light blocking stop for blocking a part of the illumination light introduced into the microscope main body from the introduction hole, provided in the front stage of the introduction hole of the microscope main body;
A microscope apparatus comprising:   The microscope apparatus according to claim 1, further comprising a lens that is provided in a front stage of the light-shielding diaphragm and makes the illumination light substantially parallel light.   The microscope apparatus according to claim 2, further comprising a light projecting tube that holds the light-shielding diaphragm and the lens, wherein the light projecting tube and the microscope main body are connected via a heat insulating member.   The microscope apparatus according to claim 3, further comprising a heat transfer member for releasing heat accumulated in the light projecting tube.   The microscope apparatus according to claim 1, wherein the microscope main body has a field stop, and an opening diameter of the light-shielding stop is larger than an opening diameter of the field stop. A vacuum chamber;
The microscope apparatus according to any one of claims 1 to 5, provided in the vacuum chamber;
A light source lamp provided outside the vacuum chamber for supplying illumination light to the microscope apparatus;
A light guide for guiding illumination light from the light source lamp to the microscope apparatus;
A substrate holder provided in the vacuum chamber for positioning and holding the substrate;
A mask holder for positioning and holding a mask provided with a desired pattern provided in the vacuum chamber;
An exposure light source for transferring the desired pattern onto the substrate through the mask;
An exposure apparatus comprising:

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