Method of manufacturing a laser cavity and electronics

Abstract

Provided is a method for manufacturing a laser cavity and electronic device. A laser cavity of an excimer laser device has a container that contains a first member and a second member, and internally houses a laser gas; and a ring-shaped sealing member that is disposed between two opposing sealing surfaces of the first member and the second member, a surface of the sealing member on the laser gas side is composed of fluorine rubber, a surface of the sealing member on the atmosphere side is composed of a film that inhibits the passage of the atmosphere, and the film has a thickness that is thicker at a position away from the two sealing surfaces and is thinner at a position close to the two sealing surfaces.

Description

[0001] This application is a divisional application of the patent application for which the title is "Laser cavity, method for manufacturing a sealing member, and method for manufacturing an electronic device", the filing date is April 23, 2018, and the application number is 201880090669.0 (international application number PCT / JP2018 / 016491). TECHNICAL FIELD

[0002] The present disclosure relates to a laser cavity and a method for manufacturing an electronic device. BACKGROUND

[0003] With the miniaturization and high integration of semiconductor integrated circuits, an improvement in resolution is required in a semiconductor exposure apparatus. Hereinafter, the semiconductor exposure apparatus will be simply referred to as an "exposure apparatus". Therefore, the shortening of the wavelength of light output from an exposure light source has been developed. In the exposure light source, a gas laser device is used instead of a conventional mercury lamp. Currently, as the gas laser device for exposure, a KrF excimer laser device that outputs ultraviolet light having a wavelength of 248 nm, and an ArF excimer laser device that outputs ultraviolet light having a wavelength of 193 nm are used.

[0004] As the current exposure technology, the following liquid immersion exposure has been put into practical use: by filling a gap between a projection lens on the side of an exposure apparatus and a wafer with a liquid, the wavelength of the appearance of the exposure light source is shortened by changing the refractive index of the gap. In the case of liquid immersion exposure using an ArF excimer laser device as an exposure light source, ultraviolet light having a wavelength of 134 nm in water is irradiated onto the wafer. This technique is called ArF liquid immersion exposure. The ArF liquid immersion exposure is also called ArF liquid immersion lithography.

[0005] The spectral line width in the natural oscillation of the KrF, ArF excimer laser device is wide, about 350 to 400 pm, and therefore, the laser (ultraviolet light) projected onto the wafer through the projection lens on the side of the exposure apparatus produces chromatic aberration, and the resolution decreases. Therefore, it is necessary to narrow the spectral line width of the laser output from the gas laser device to the extent that the chromatic aberration can be ignored. The spectral line width is also called the spectral width. Therefore, a line narrow module having a narrow band element is provided in the laser resonator of the gas laser device, and the narrow band of the spectral width is achieved by the line narrow module. In addition, the narrow band element can be an etalon or a grating, etc. Such a laser device in which the spectral width is narrowed is called a narrow band laser device.

[0006] PRIOR ART DOCUMENTS

[0007] PATENT DOCUMENTS

[0008] Patent Document 1: Japanese Patent Application Publication No. 10-256625 SUMMARY

[0009] A laser chamber of an excimer laser device according to one aspect of the present disclosure has a container including a first member and a second member, which internally houses a laser gas, and a ring-shaped sealing member disposed between two opposing sealing surfaces of the first member and the second member, a surface of the sealing member on the laser gas side being composed of a fluorine rubber, and a surface of the sealing member on the atmospheric side being composed of a film that suppresses the transmission of the atmosphere, the film having a thickness that is thicker at a position away from the two sealing surfaces and thinner at a position close to the two sealing surfaces.

[0010] A method of manufacturing an electronic device according to one aspect of the present disclosure includes a step of generating laser light by an excimer laser device including a laser chamber, outputting the laser light to an exposure device, and exposing the laser light on a photosensitive substrate in the exposure device to manufacture an electronic device, wherein the laser chamber has a container including a first member and a second member, which internally houses a laser gas, and a ring-shaped sealing member disposed between two opposing sealing surfaces of the first member and the second member, a surface of the sealing member on the laser gas side being composed of a fluorine rubber, and a surface of the sealing member on the atmospheric side being composed of a film that suppresses the transmission of the atmosphere, the film having a thickness that is thicker at a position away from the two sealing surfaces and thinner at a position close to the two sealing surfaces. BRIEF DESCRIPTION OF DRAWINGS

[0011] Hereinafter, several embodiments of the present disclosure will be described as simple examples with reference to the drawings.

[0012] Figure 1A The structure of the excimer laser device of the comparative example is schematically shown.

[0013] Figure 1B The structure of the excimer laser device of the comparative example is schematically shown.

[0014] Figure 2 is a cross-sectional view showing a structure example of a sealing mechanism using a sealing member in the comparative example.

[0015] Figure 3 is a cross-sectional view showing a part of the sealing structure shown in Figure 2

[0016] Figure 4 is a cross-sectional view showing a part of the sealing structure in the first embodiment of the present disclosure.

[0017] Figure 5 The cross section of the sealing member in the second embodiment of the present disclosure is schematically shown.

[0018] Figure 6A The structure of the excimer laser device of the third embodiment of the present disclosure is schematically shown. ​

[0019] Figure 6B The structure of the excimer laser device of Embodiment 3 of the present disclosure is schematically shown.

[0020] Figure 7A The jig set used in the manufacturing method of the sealing member of Embodiment 4 of the present disclosure is schematically shown.

[0021] Figure 7B is a sectional view showing the internal structure of the jig set shown in Figure 7A

[0022] Figure 7C The manufacturing method of the sealing member of Embodiment 4 of the present disclosure is schematically shown.

[0023] Figure 7D The manufacturing method of the sealing member of Embodiment 4 of the present disclosure is schematically shown.

[0024] Figure 8A The manufacturing method of the sealing member of Embodiment 5 of the present disclosure is schematically shown.

[0025] Figure 8B The manufacturing method of the sealing member of Embodiment 5 of the present disclosure is schematically shown.

[0026] Figure 8C The manufacturing method of the sealing member of Embodiment 5 of the present disclosure is schematically shown.

[0027] Figure 8D The manufacturing method of the sealing member of Embodiment 5 of the present disclosure is schematically shown.

[0028] Figure 9 The structure of the exposure device connected to the excimer laser device is schematically shown. DETAILED DESCRIPTION

[0029] <CONTENT>

[0030] 1. Comparative Example

[0031] 1.1 Structure of excimer laser device

[0032] 1.2 Operation of excimer laser device

[0033] 1.3 Sealing member

[0034] 1.3.1 Sealing structure of retainer 16a and optical crystal 16

[0035] 1.3.2 Sealing structure of container member 10b and window 10f

[0036] 1.3.3 Sealing structure of other container members ​

[0037] 1.4 Problem to be Solved

[0038] 2. Sealing member having film with inhibition of atmospheric permeation

[0039] 2.1 Structure

[0040] 2.2 Action

[0041] 2.3 Others

[0042] 3. Sealing member having multilayer film

[0043] 4. Examples of container member

[0044] 5. Clip set

[0045] 5.1 Structure

[0046] 5.2 Action

[0047] 6. Method for forming film having multiple layers

[0048] 7. Others

[0049] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The embodiments described below show several examples of the present disclosure, and do not limit the present disclosure. Furthermore, the structures and actions described in each of the embodiments are not necessarily all the structures and actions essential to the present disclosure. In addition, the same reference numerals are assigned to the same structural elements, and repeated description is omitted.

[0050] 1. Comparative Example

[0051] 1.1 Structure of excimer laser device

[0052] Figure 1A And Figure 1B The structure of the excimer laser device of the comparative example is schematically shown. In Figure 1A , the internal structure of the excimer laser device is shown as viewed from a direction that is substantially perpendicular to the discharge direction between the pair of discharge electrodes 11a and 11b and that is substantially perpendicular to the traveling direction of the laser light output from the output coupling mirror 15. In Figure 1B , the internal structure of the excimer laser device is shown as viewed from a direction that is substantially parallel to the traveling direction of the laser light output from the output coupling mirror 15. The traveling direction of the laser light output from the output coupling mirror 15 is set as the +Z direction. The discharge direction between the discharge electrodes 11a and 11b is set as the +V direction or the -V direction. The direction perpendicular to these two directions is set as the +H direction or the -H direction. The -V direction is substantially in line with the direction of gravity.

[0053] As Figure 1AAs shown, the excimer laser device is used in conjunction with the exposure apparatus 100. Laser light output from the excimer laser device is incident on the exposure apparatus 100. The exposure apparatus 100 includes an exposure apparatus control unit 110. The exposure apparatus control unit 110 is configured to control the exposure apparatus 100. The exposure apparatus control unit 110 is configured to send target pulse energy setting data and emission trigger signals to the laser control unit 30 included in the excimer laser device.

[0054] The excimer laser device includes a laser cavity 10, a charger 12, a pulse power module 13, a narrowband module 14, an output coupling mirror 15, an energy monitor 17, a crossflow fan 21, a motor 22, a heat exchanger 23, and a laser control unit 30. The laser control unit 30 provides overall control of the excimer laser device.

[0055] The laser cavity 10 includes container components 10a and 10b. The laser cavity 10 is configured in the optical path of a laser resonator formed by a narrowband module 14 and an output coupling mirror 15. Two windows 10f and 10g are provided in the laser cavity 10. The laser cavity 10 houses discharge electrodes 11a and 11b. The laser cavity 10 houses a laser gas serving as the laser medium. The laser gas may include, for example, argon, fluorine, and neon. Alternatively, the laser gas may include, for example, krypton, fluorine, and neon.

[0056] An opening is formed in a portion of the container component 10b, which is blocked by an electrically insulating portion 20. The electrically insulating portion 20 supports the discharge electrode 11a. A plurality of conductive portions 20a are embedded in the electrically insulating portion 20. The conductive portions 20a are electrically connected to the discharge electrode 11a.

[0057] A reflux plate 10c is disposed inside the laser cavity 10. The container component 10b and the reflux plate 10c are connected via... Figure 1B Wiring section 10d and wiring section 10e are electrically connected. Return plate 10c supports discharge electrode 11b. Return plate 10c is electrically connected to discharge electrode 11b.

[0058] like Figure 1B As shown, the reflux plate 10c is in Figure 1A The inner and near-front sides of the paper have gaps for the laser gas to pass through.

[0059] A crossflow fan 21 is disposed inside the laser cavity 10. The rotation shaft of the crossflow fan 21 is connected to a motor 22 disposed outside the laser cavity 10. The motor 22 causes the crossflow fan 21 to rotate. Thus, as Figure 1B As indicated by arrow A, the laser gas circulates inside the laser cavity 10. The heat exchanger 23 removes the heat energy from the laser gas, which becomes hot due to the discharge, to the outside of the laser cavity 10.

[0060] The charger 12 holds electric energy for supplying to the pulse power module 13. The pulse power module 13 includes a charging capacitor and a switch 13a, which are not shown. The charging capacitor of the pulse power module 13 is connected to the charger 12. The discharge electrode 11a is connected to the charging capacitor of the pulse power module 13.

[0061] The narrowbanding module 14 includes a wavelength selection element such as a prism 14a and a grating 14b. Instead of the narrowbanding module 14, a high reflection mirror can be used.

[0062] The output coupling mirror 15 is composed of a partial mirror.

[0063] The energy monitor 17 includes a beam splitter 17a, a condenser lens 17b, and a light sensor 17c. The beam splitter 17a is disposed in the optical path of the laser light output from the output coupling mirror 15. The beam splitter 17a is configured to transmit a part of the laser light output from the output coupling mirror 15 to the exposure apparatus 100 with high transmittance, and to reflect the other part. The condenser lens 17b and the light sensor 17c are disposed in the optical path of the laser light reflected by the beam splitter 17a.

[0064] 1.2 Operation of the excimer laser apparatus

[0065] The laser control section 30 receives the setting data of the target pulse energy and the light emission trigger signal from the exposure apparatus control section 110. The laser control section 30 transmits the setting data of the charging voltage to the charger 12 in accordance with the setting data of the target pulse energy received from the exposure apparatus control section 110. Further, the laser control section 30 transmits the trigger signal to the pulse power module 13 in accordance with the light emission trigger signal received from the exposure apparatus control section 110.

[0066] The pulse power module 13 generates a pulse-shaped high voltage from the electric energy charged by the charger 12 in accordance with the trigger signal received from the laser control section 30, and applies the high voltage between the discharge electrodes 11a and 11b.

[0067] The high voltage is applied between the discharge electrodes 11a and 11b, and discharge occurs between the discharge electrodes 11a and 11b. The laser gas in the laser cavity 10 is excited by the energy of the discharge, and transitions to a high energy level. Then, when the excited laser gas transitions to a low energy level, light of a wavelength corresponding to the difference between the energy levels is emitted.

[0068] Light generated in the laser cavity 10 is emitted to the outside of the laser cavity 10 via the windows 10f and 10g. The light emitted from the window 10f of the laser cavity 10 is expanded in beam width by the prism 14a, and is incident on the grating 14b. The light incident on the grating 14b from the prism 14a is reflected by the plurality of grooves of the grating 14b, and is diffracted in a direction corresponding to the wavelength of the light. The grating 14b is disposed in a Littrow configuration so as to make the incident angle of the light incident on the grating 14b from the prism 14a coincide with the diffraction angle of the diffracted light of the desired wavelength. Thereby, light in the vicinity of the desired wavelength is returned to the laser cavity 10 via the prism 14a.

[0069] The output coupling mirror 15 transmits a part of the light emitted from the window 10g of the laser cavity 10 to the outside, and reflects the other part to return to the laser cavity 10.

[0070] Thus, the light emitted from the laser cavity 10 is reciprocated between the narrowbanding module 14 and the output coupling mirror 15. The light is amplified each time it passes through the discharge space between the discharge electrodes 11a and 11b. Further, the light is narrowbanded each time it is folded back at the narrowbanding module 14. The light that is narrowbanded as a result of the laser oscillation is output as laser light from the output coupling mirror 15.

[0071] The condenser lens 17b included in the energy monitor 17 condenses the laser light reflected by the beam splitter 17a on the light sensor 17c. The light sensor 17c transmits an electric signal corresponding to the pulse energy of the laser light condensed by the condenser lens 17b to the laser control section 30 as measurement data.

[0072] The laser control section 30 receives the measurement data from the energy monitor 17. The laser control section 30 performs feedback control of the charging voltage set in the charger 12 based on the measurement data of the pulse energy received from the energy monitor 17 and the setting data of the target pulse energy received from the exposure device control section 110.

[0073] 1.3 Sealing member

[0074] Figure 2 is a cross-sectional view showing a structure example of a sealing mechanism using a sealing member in a comparative example. Figure 2 A case where the container member 10b and the window 10f are sealed, and the holder 16a of the window 10f and the optical crystal 16 are sealed is shown.

[0075] 1.3.1 Sealing configuration of the holder 16a and the optical crystal 16

[0076] The window 10f includes the optical crystal 16, and the holders 16a and 16b. The optical crystal 16 is held between the holders 16a and 16b. The holder 16a has an opening 16h. The holder 16a has a groove 16i around the opening 16h. The holder 16b has an opening 16k.

[0077] A sealing member 16j is arranged between the optical crystal 16 and the holder 16a. The sealing member 16j is arranged in the groove 16i. The sealing member 16j is a circular ring-shaped O-ring. A buffer material 16e is arranged between the optical crystal 16 and the holder 16b.

[0078] The holder 16a and the holder 16b are fixed to each other by bolts or the like not shown around the optical crystal 16. The optical crystal 16 is composed of, for example, a crystal of calcium fluoride, and is formed in a disc shape. The holder 16b is composed of, for example, ceramic or aluminum. The buffer material 16e is composed of, for example, stainless steel or aluminum.

[0079] By being configured as described above, the optical crystal 16 blocks the opening 16h of the holder 16a. The opening 16h is closed by the sealing member 16j arranged between the two opposing sealing surfaces of the optical crystal 16 and the holder 16a, and the laser gas side and the atmospheric side are shut off.

[0080] 1.3.2 Sealing configuration of the container member 10b and the window 10f

[0081] The container member 10b has an opening 10h.

[0082] The container member 10b has a groove 10i around the opening 10h. A sealing member 10j is arranged in the groove 10i. The sealing member 10j is a circular ring-shaped O-ring. Around the groove 10i and the sealing member 10j, the container member 10b and the holders 16a and 16b of the window 10f are fixed to each other by bolts or the like not shown. In this example, the container member 10b corresponds to the first member in the present disclosure, and the window 10f corresponds to the second member in the present disclosure. The container member 10b is composed of, for example, a metal such as nickel-plated aluminum. The holders 16a and 16b of the window 10f are composed of, for example, ceramic or aluminum.

[0083] By being configured as described above, the window 10f blocks the opening 10h of the container member 10b. The opening 10h is closed by the sealing member 10j arranged between the two opposing sealing surfaces of the container member 10b and the window 10f, and the laser gas side and the atmospheric side are shut off.

[0084] The pulsed laser can pass through the opening 10h of the container member 10b, the opening 16h of the holder 16a, the central portion of the optical crystal 16, and the opening 16k of the holder 16b.

[0085] 1.3.3 Sealing configuration of other container members

[0086] Referring again to Figure 1A and Figure 1BThe electrically insulating portion 20 is sealed by the ring-shaped sealing member 10k arranged around the opening of the container member 10b. Around the sealing member 10k, the container member 10b and the electrically insulating portion 20 are fixed to each other by bolts or the like not shown. In this case, the container member 10b corresponds to the first member in the present disclosure, and the electrically insulating portion 20 corresponds to the second member in the present disclosure. The container member 10b is composed of, for example, a metal such as nickel-plated aluminum. The electrically insulating portion 20 is composed of, for example, ceramic.

[0087] By being thus configured, the electrically insulating portion 20 blocks the opening of the container member 10b. The laser gas side and the atmospheric side are shut off by the sealing member 10k arranged between the opposing two sealing surfaces of the container member 10b and the electrically insulating portion 20.

[0088] Further, the container member 10b is sealed by the ring-shaped sealing member 10m arranged around the opening of the container member 10a. Around the sealing member 10m, the container member 10a and the container member 10b are fixed to each other by bolts or the like not shown. In this case, the container member 10a corresponds to the first member in the present disclosure, and the container member 10b corresponds to the second member in the present disclosure. The container members 10a and 10b are composed of, for example, a metal such as nickel-plated aluminum.

[0089] By being thus configured, the container member 10b blocks the opening of the container member 10a. The laser gas side and the atmospheric side are shut off by the sealing member 10m arranged between the opposing two sealing surfaces of the container member 10a and the container member 10b.

[0090] 1.4 Problem to be Solved

[0091] Figure 3 is enlarged Figure 2 A cross-sectional view of a part of the sealing structure shown in FIG. 1. In the metal that constitutes the container member 10b and the ceramic that constitutes the retainer 16a of the window 10f, the thermal expansion rates are different. Therefore, as the sealing member 10j, it is preferable to use an elastomer. By using an elastomer as the sealing member 10j, it is possible to absorb the shift caused by the difference in thermal expansion between the container member 10b and the retainer 16a of the window 10f. As the sealing member 10j, for example, it is preferable to use a fluorine rubber that is resistant to fluorine gas. As the fluorine rubber, for example, it is preferable to be a fluoroelastomer or Viton (registered trademark). With regard to the sealing member 16j described above, it is also preferable to be the same elastomer in order to suppress damage to the optical crystal 16. Figure 2 A cross-sectional view of a part of the sealing structure shown in FIG. 1. In the metal that constitutes the container member 10b and the ceramic that constitutes the retainer 16a of the window 10f, the thermal expansion rates are different. Therefore, as the sealing member 10j, it is preferable to use an elastomer. By using an elastomer as the sealing member 10j, it is possible to absorb the shift caused by the difference in thermal expansion between the container member 10b and the retainer 16a of the window 10f. As the sealing member 10j, for example, it is preferable to use a fluorine rubber that is resistant to fluorine gas. As the fluorine rubber, for example, it is preferable to be a fluoroelastomer or Viton (registered trademark). With regard to the sealing member 16j described above, it is also preferable to be the same elastomer in order to suppress damage to the optical crystal 16.

[0092] However, the sealing component 10j sometimes fails to reduce atmospheric permeability from the atmospheric side to the interior of the laser cavity 10 to zero. There are two atmospheric permeation paths within the sealing component 10j. The first permeation path is along the sealing surface of the container component 10b or the holder 16a, which is connected to the sealing component 10j. Figure 3 The second transmission path is indicated by a dashed arrow. The second transmission path is the transmission path through the interior of the sealing component 10j. Figure 3 The arrows are indicated by solid lines. When an elastomer is used as the sealing component 10j, the second transmission path sometimes allows more than 10 times the atmospheric permeability compared to the first transmission path. For example, atmospheric oxygen or water vapor sometimes permeates through the elastomer. When atmospheric gas permeates into the laser cavity 10 from the atmospheric side, the laser gas inside the laser cavity 10 is contaminated. Therefore, the replacement gas consumption sometimes increases.

[0093] In the embodiments described below, a membrane that inhibits atmospheric permeation is formed on the atmospheric side surface of the sealing member. By using the sealing member having this membrane, atmospheric permeation through the interior of the sealing member 10j is inhibited, thus suppressing contamination by laser gas.

[0094] 2. A sealing component with a membrane that inhibits atmospheric permeation.

[0095] 2.1 Structure

[0096] Figure 4 This is a cross-sectional view showing a portion of the sealing structure in the first embodiment of this disclosure. Figure 4 Referring to the first embodiment, it is shown that... Figure 3 A significant portion of the cross-section. For example... Figure 4 As shown, a film 10n is formed on the atmospheric side surface of the sealing member 10j. No film 10n is formed on the laser gas side surface of the sealing member 10j, and the fluororubber is exposed on the laser gas side surface of the sealing member 10j. No film 10n is also formed on the surface of the sealing member 10j that contacts the sealing surfaces of the container member 10b and the retainer 16a, and the fluororubber contacts both the container member 10b and the retainer 16a.

[0097] Membrane 10n may, for example, comprise fluorine-containing diamond-like carbon. Alternatively, membrane 10n may comprise at least one of Al2O3, SiO2, and TiO.

[0098] The thickness of the preferred membrane 10n is, for example, 0.1 μm or more and 0.3 μm or less. The thickness of the preferred membrane 10n is formed such that it is thicker at a position away from the sealing surface of the container component 10b and the holder 16a, and thinner at a position close to the sealing surface of the container component 10b and the holder 16a.

[0099] 2.2 Function

[0100] In the first embodiment, by forming a membrane 10n that inhibits atmospheric permeation on the atmospheric side surface of the sealing member 10j, the amount of air permeating into the interior of the sealing member 10j is reduced to approximately 50% or less compared to the case where no membrane 10n is formed. Even if cracks occur on the surface of the membrane 10n, the vast majority of the atmospheric side surface of the sealing member 10j is covered by the membrane 10n, therefore, the impact on the performance of inhibiting atmospheric permeation is considered to be minimal.

[0101] Furthermore, according to the first embodiment, similar to the comparative example described above, the amount of air passing through the sealing surface of the container component 10b or the holder 16a that is in contact with the sealing member 10j can still be relatively small. Furthermore, the fastening force of the holder 16a relative to the container component 10b can be the same as the fastening force in the comparative example described above.

[0102] Furthermore, when the same film is formed on the surface of the sealing member 10j that is in contact with the sealing surfaces of the container member 10b and the retainer 16a, the sealing performance may be lost if the film cracks. Therefore, it is preferable not to form a film on the surface of the sealing member 10j that is in contact with the sealing surfaces of the container member 10b and the retainer 16a.

[0103] Furthermore, according to the first embodiment, the fluororubber is exposed on the surface of the sealing member 10j on the laser gas side, thus enabling it to have the same resistance to fluorine gas as the comparative example described above. Additionally, the film 10n has lower resistance to fluorine gas; therefore, it is preferable that the film 10n is not formed on the surface of the sealing member 10j on the laser gas side.

[0104] 2.3 Other

[0105] Figure 3 The diagram shows a sealing member 10j disposed between the container component 10b and the retainer 16a of the window 10f; however, this disclosure is not limited thereto.

[0106] It can also be in Figure 2 A membrane that inhibits atmospheric permeation is formed on the atmospheric side surface of the sealing member 16j, which is disposed between the optical crystal 16 and the holder 16a. Alternatively,... Figure 1A and Figure 1B A membrane that inhibits atmospheric permeation is formed on the atmospheric side surface of the sealing member 10k, which is disposed between the container member 10b and the electrical insulation portion 20. Furthermore, it is also possible to... Figure 1A and Figure 1B The surface of the sealing member 10m, which is disposed between container member 10a and container member 10b, is formed with a membrane that inhibits atmospheric permeation.

[0107] 3. Sealing components with multi-layer membranes

[0108] Figure 5A cross section of the sealing member in the second embodiment of the present disclosure is schematically shown. The film 10n formed in the sealing member 10j includes a plurality of layers that suppress the passage of the atmosphere.

[0109] The plurality of layers includes a first layer L1 and a second layer L2 located on the side closer to the atmosphere than the first layer L1. The plurality of layers is not limited to two layers, and can include three or more layers. In the case where the plurality of layers is included, the thickness of the film 10n is preferably 0.1 μm or more and 0.3 μm or less.

[0110] The area of the second layer L2 is preferably smaller than the area of the first layer L1. Further, the thickness of the second layer L2 is preferably smaller than the thickness of the first layer L1. Thus, even if stress is applied to the sealing member 10j, peeling or breaking of the film 10n can be suppressed.

[0111] The other aspects are the same as those of the first embodiment.

[0112] 4. Examples of container member

[0113] Figure 6A and Figure 6B The structure of an excimer laser device of the third embodiment of the present disclosure is schematically shown. Figure 6A and Figure 6B are cross-sectional views of portions corresponding to Figure 1A and Figure 1B respectively. However, in Figure 6A , the illustration of a laser resonator or the like disposed outside the laser cavity 10 is omitted.

[0114] In the third embodiment, the laser cavity 10 includes container members 10p, 10q, and 10r. The container member 10p is a cylindrical member. The container members 10q and 10r are disposed at the openings of the +Z direction and -Z direction ends of the container member 10p, respectively.

[0115] The container member 10q is sealed by a ring-shaped sealing member 10s disposed around the opening of the +Z direction end of the container member 10p. Around the sealing member 10s, the container member 10p and the container member 10q are fixed to each other by bolts or the like not shown. In this case, the container member 10p corresponds to the first member in the present disclosure, and the container member 10q corresponds to the second member in the present disclosure. The container members 10p and 10q are composed of, for example, a metal such as nickel-plated aluminum.

[0116] By being thus configured, the container member 10q plugs the opening of the container member 10p. By the sealing member 10s disposed between the opposing two sealing surfaces of the container member 10p and the container member 10q, the laser gas side and the atmosphere side are shut off.

[0117] A film that suppresses the passage of the atmosphere can also be formed on the surface of the sealing member 10s on the atmosphere side.

[0118] Likewise, the container member 10r is sealed by the ring-shaped sealing member 10t that is arranged around the opening of the end portion of the container member 10p in the -Z direction. The container member 10p and the container member 10r are fixed to each other by bolts or the like, not shown, around the sealing member 10t. In this case, the container member 10p corresponds to the first member in the present disclosure, and the container member 10r corresponds to the second member in the present disclosure. The container members 10p and 10r are composed of, for example, a metal such as nickel-plated aluminum.

[0119] By being thus configured, the container member 10r plugs the opening of the container member 10p. The laser gas side and the atmosphere side are shut off by the sealing member 10t that is arranged between the opposing two sealing surfaces of the container member 10p and the container member 10r.

[0120] A film that suppresses the passage of the atmosphere can also be formed on the surface of the sealing member 10s on the atmosphere side.

[0121] The other aspects are the same as those of the first and second embodiments.

[0122] 5. Clamp set

[0123] 5.1 Structure

[0124] Figure 7A A clamp set used in a manufacturing method of a sealing member of the fourth embodiment of the present disclosure is schematically shown. Figure 7B is a sectional view showing the internal structure of the clamp set shown in Figure 7A

[0125] The clamp set includes first to third clamps 61 to 63. The first clamp 61 has a substantially cylindrical shape. The first clamp 61 has an external thread portion 61a and 61b at both ends in the axial direction. The first clamp 61 has a tapered portion 61c near the center in the axial direction. The tapered portion 61c is shaped so that the diameter decreases as it approaches the external thread portion 61a along the axial direction of the first clamp 61.

[0126] A cylindrical portion 61d having a diameter slightly larger than those of the external thread portion 61a and the tapered portion 61c is arranged between the external thread portion 61a and the tapered portion 61c. A cylindrical portion 61e having a diameter slightly larger than those of the external thread portion 61b and the tapered portion 61c is arranged between the external thread portion 61b and the tapered portion 61c.

[0127] The second clamp 62 is a cylindrical member arranged around the outer periphery of the cylindrical portion 61d of the first clamp 61. The second clamp 62 is configured to be movable in the axial direction of the first clamp 61.

[0128] ​The third jig 63 is a cylindrical member configured to the outer periphery of the cylindrical portion 61e of the first jig 61. The third jig 63 is configured to be movable in the axial direction of the first jig 61.

[0129] The nut 64 is coupled to the external thread portion 61a. By rotating the nut 64 around the axis of the first jig 61, the nut 64 is moved in the axial direction of the first jig 61. Thus, the position of the second jig 62 can be changed.

[0130] The nut 65 is coupled to the external thread portion 61b. By rotating the nut 65 around the axis of the first jig 61, the nut 65 is moved in the axial direction of the first jig 61. Thus, the position of the third jig 63 can be changed.

[0131] By changing the position of the second jig 62 or the position of the third jig 63, the interval between the second jig 62 and the third jig 63 can be changed.

[0132] The mechanism for moving the second jig 62 and the third jig 63 in the axial direction of the first jig 62 can not use the nuts 64 and 65.

[0133] 5.2 Operation

[0134] The following process is performed using the jig set including the first to third jigs 61 to 63, to manufacture the annular sealing member 10j having the film on a part of the surface.

[0135] As the first process, as shown in Figure 7A and Figure 7B the annular member 10u constituting the sealing member 10j is fitted to the outer periphery of the tapered portion 61c of the first jig 61.

[0136] As the second process, as shown in Figure 7C the annular member 10u is sandwiched by the second jig 62 and the third jig 63, so that the outer peripheral surface of the annular member 10u is exposed between the second jig 62 and the third jig 63.

[0137] As the third process, as shown in Figure 7D the film 10n is formed on the outer peripheral surface of the annular member 10u in the state where the outer peripheral surface of the annular member 10u is exposed between the second jig 62 and the third jig 63.

[0138] As shown in Figure 4 the minor axis length of the cross section of the annular member 10u when used as the sealing member is A. In the above second process, the interval between the second jig 62 and the third jig 63 can be adjusted in the state where the annular member 10u is pressed in the axial direction of the first jig 61 by the second jig 62 and the third jig 63. Thus, the minor axis length A of the cross section of the annular member 10u can be set to a predetermined value.

[0139] As Figure 4 shown, let the long axis length of the cross section of the annular member 10u when used as a sealing member be B, and let the contact length of the annular member 10u with the sealing surface be d. In the above-mentioned first process, the inner peripheral surface of the annular member 10u can also be brought into contact with the tapered portion 61c. Furthermore, in the second process, the contact position of the annular member 10u with the tapered portion 61c is adjusted by adjusting the position of the second jig 62 and the position of the third jig 63, respectively. The inner diameter dimension of the annular member 10u is specified by the contact position of the annular member 10u with the tapered portion 61c. Thus, the contact length d of the annular member 10u with the sealing surface can be adjusted separately from the long axis length B of the cross section of the annular member 10u.

[0140] The film 10n is formed by this size adjustment, whereby the film 10n can be formed so as to match the shape of the sealing member 10j when the sealing member 10j is actually used.

[0141] When the diameter of the cross section of the sealing member 10j in a state in which the sealing member 10j is not compressed is L, as shown in Figure 7A and Figure 7B When the width of the groove 10i is D, as shown in Figure 4 the following relationship is preferable.

[0142] D > L 2 when d ≒ L 2 / 2A

[0143] D ≤ L 2 when d ≒ D / 2

[0144] 6. Method of forming a film having multiple layers

[0145] Figure 8A through Figure 8D A manufacturing method of a sealing member of the fifth embodiment of the present disclosure is schematically shown. The jig set used in the fifth embodiment is the same as the jig set described with reference to Figure 7A through Figure 7D In the fifth embodiment, a film including multiple layers is formed by the following method, and a sealing member is manufactured.

[0146] As a first process, the annular member 10u that constitutes the sealing member 10j is fitted to the outer periphery of the tapered portion 61c of the first jig 61. This is the same as the case described with reference to Figure 7A and Figure 7B

[0147] As a second process, the annular member 10u is sandwiched by the second jig 62 and the third jig 63 so as to become a state in which the outer peripheral surface of the annular member 10u is exposed between the second jig 62 and the third jig 63. At this time, as shown in Figure 8A the position of the second jig 62 is set to a first specified position. The first specified position is in​Figure 8A The distance P1 is shown from the lower end of the outer thread portion 61a. Further, the interval between the third jig 63 and the second jig 62 is made the first prescribed distance D1.

[0148] As the third step, as shown in FIG. 6, the first layer L1 is formed on the outer peripheral surface of the annular member 10u in a state in which the outer peripheral surface of the annular member 10u is exposed between the second jig 62 and the third jig 63. In order to form the first layer L1, for example, a plasma ion implantation film formation method can be used. For example, as shown in FIG. 7, a jig set in which the annular member 10u is installed is housed inside a film formation chamber 50 having a gas introduction path 51, a power source 52, a plasma electrode 53, and a ground 54. A film formation gas is introduced from the gas introduction path 51 to the film formation chamber 50, and the film formation gas is plasma- ized by electric energy supplied from the power source 52 to the plasma electrode 53. Ions of the film formation gas are accumulated on the outer peripheral surface of the annular member 10u, and thereby the first layer L1 is formed. Figure 8B Figure 8B As shown in FIG. 6, the first layer L1 is formed on the outer peripheral surface of the annular member 10u in a state in which the outer peripheral surface of the annular member 10u is exposed between the second jig 62 and the third jig 63. In order to form the first layer L1, for example, a plasma ion implantation film formation method can be used. For example, as shown in FIG. 7, a jig set in which the annular member 10u is installed is housed inside a film formation chamber 50 having a gas introduction path 51, a power source 52, a plasma electrode 53, and a ground 54. A film formation gas is introduced from the gas introduction path 51 to the film formation chamber 50, and the film formation gas is plasma- ized by electric energy supplied from the power source 52 to the plasma electrode 53. Ions of the film formation gas are accumulated on the outer peripheral surface of the annular member 10u, and thereby the first layer L1 is formed.

[0149] The third step further includes a step of moving the second jig 62 and the third jig 63 after the first layer L1 is formed. The second jig 62 is moved to a second prescribed position in a direction farther from the third jig 63 than the above-described first prescribed position. The second prescribed position is shown in FIG. 8 as a distance P2 from the lower end of the outer thread portion 61a. Further, the interval between the third jig 63 and the second jig 62 is made a second prescribed distance D2 shorter than the above-described first prescribed distance D1. Thereby, as shown in FIG. 9, the annular member 10u is moved to a position closer to the outer thread portion 61a than the state shown in FIG. 8, that is, to a position in which the diameter of the tapered portion 61c is smaller. Further, as shown in FIG. 10, the annular member 10u is brought into a state in which it is compressed in the axial direction of the first jig 61 compared to the state shown in FIG. 8. Thereby, the contact length d of the annular member 10u with the sealing surface becomes longer. Figure 8C Figure 8C Figure 8A Figure 8A

[0150] The third step further includes a step of moving the second jig 62 and the third jig 63 after the first layer L1 is formed. The second jig 62 is moved to a second prescribed position in a direction farther from the third jig 63 than the above-described first prescribed position. The second prescribed position is shown in FIG. 8 as a distance P2 from the lower end of the outer thread portion 61a. Further, the interval between the third jig 63 and the second jig 62 is made a second prescribed distance D2 shorter than the above-described first prescribed distance D1. Thereby, as shown in FIG. 9, the annular member 10u is moved to a position closer to the outer thread portion 61a than the state shown in FIG. 8, that is, to a position in which the diameter of the tapered portion 61c is smaller. Further, as shown in FIG. 10, the annular member 10u is brought into a state in which it is compressed in the axial direction of the first jig 61 compared to the state shown in FIG. 8. Thereby, the contact length d of the annular member 10u with the sealing surface becomes longer. Figure 8D Figure 8B Figure 5 Figure 8C ​​​​​​​​​

[0151] As the plurality of layers, not limited to 2 layers, 3 or more layers can be formed. The layer can be smaller in thickness as it is more outside. The layer can be smaller in area as it is more outside.

[0152] The sealing member 10j is manufactured as described above, whereby, as described with reference to Figure 5 the sealing member 10j, peeling or breaking of the film 10n can be suppressed even if stress is applied thereto.

[0153] 7. Other

[0154] Figure 9 The structure of an exposure apparatus 100 connected to the excimer laser device 1 is schematically shown. As described above, the excimer laser device 1 generates laser light and outputs it to the exposure apparatus 100.

[0155] In Figure 9 , the exposure apparatus 100 includes an illumination optical system 41 and a projection optical system 42. The illumination optical system 41 illuminates a reticle pattern of a reticle stage RT with laser light incident from the excimer laser device 1. The projection optical system 42 reduces and projects the laser light that has passed through the reticle, so as to be imaged on an unillustrated workpiece provided on a workpiece stage WT. The workpiece is a photosensitive substrate such as a semiconductor wafer on which a photoresist is coated. The exposure apparatus 100 moves the reticle stage RT and the workpiece stage WT in parallel in synchronization, whereby the laser light that reflects the reticle pattern is exposed on the workpiece. By the above exposure process, a device pattern is transferred on the semiconductor wafer, whereby an electronic device can be manufactured.

[0156] The above description is not a limitation but a simple example. Therefore, it is understood by those skilled in the art that modifications can be made to the embodiments of the present disclosure without departing from the scope of the claims. Further, it is understood by those skilled in the art that the embodiments of the present disclosure are used in combination.

[0157] The terms used throughout the specification and claims should be interpreted as "non-limiting" terms unless explicitly stated otherwise. For example, the term such as "comprising" or "comprised of" should be interpreted as "not limited to the part recited as included". The term such as "having" should be interpreted as "not limited to the part recited as having". Further, the indefinite article "a" should be interpreted as meaning "at least one" or "one or more than one". Further, the term such as "at least one of A, B, and C" should be interpreted as "A", "B", "C", "A+B", "A+C", "B+C", or "A+B+C". Further, it should be interpreted as further including a combination of parts other than "A", "B", and "C".

Claims

1. A laser cavity of an excimer laser apparatus, wherein, The laser cavity has: a container including a first member and a second member, which internally houses a laser gas; and a ring-shaped sealing member disposed between two opposing sealing surfaces of the first member and the second member, a surface of the sealing member on the laser gas side is composed of fluorine rubber, a surface of the sealing member on the atmospheric side is composed of a film that suppresses the transmission of the atmosphere, the film has a thickness that is thicker at a position away from the two sealing surfaces and is thinner at a position close to the two sealing surfaces, the film is not formed on a surface of the sealing member that is in contact with the two sealing surfaces.

2. The laser cavity according to claim 1, wherein the surfaces of the sealing member that are in contact with the two sealing surfaces and on which the film is not formed are each composed of fluorine rubber.

3. The laser cavity according to claim 1, wherein the film contains fluorine-containing diamond-like carbon.

4. The laser cavity according to claim 1, wherein the film contains at least one of Al2O3, SiO2, and TiO.

5. The laser cavity according to claim 1, wherein the film has a thickness of 0.1 μm or more and 0.3 μm or less.

6. The laser cavity according to claim 1, wherein the film contains a plurality of layers that suppress the transmission of the atmosphere.

7. The laser cavity according to claim 6, wherein the plurality of layers include a first layer and a second layer located at a position closer to the atmospheric side than the first layer, the second layer has an area smaller than that of the first layer.

8. The laser cavity according to claim 6, wherein the plurality of layers include a first layer and a second layer located at a position closer to the atmospheric side than the first layer, the second layer has a thickness smaller than that of the first layer.

9. The laser cavity according to claim 1, wherein the first member is composed of metal, the second member is composed of ceramic.

10. The laser cavity according to claim 1, wherein the first member is composed of metal, the second member includes an optical element through which the laser passes.

11. The laser cavity according to claim 1, wherein both the first member and the second member are composed of metal.

12. A method for manufacturing an electronic device, comprising the steps of: generating a laser by an excimer laser device including a laser cavity, outputting the laser to an exposure device, exposing the laser on a photosensitive substrate in the exposure device to manufacture an electronic device, wherein the laser cavity has: a container including a first member and a second member, which internally houses a laser gas; and a ring-shaped sealing member disposed between two opposing sealing surfaces of the first member and the second member, a surface of the sealing member on the laser gas side is composed of fluorine rubber, a surface of the sealing member on the atmospheric side is composed of a film that suppresses the transmission of the atmosphere, the film has a thickness that is thicker at a position away from the two sealing surfaces and is thinner at a position close to the two sealing surfaces, the film is not formed on a surface of the sealing member that is in contact with the two sealing surfaces.

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