Cavity device and method of manufacturing an electronic

Abstract

The cavity device (CH) has an inner housing (50) that contains a passage through which light generated in an inner space of the inner housing by excitation of a laser gas passes, and an outer housing (70) that surrounds at least a portion of the inner housing (50) from the side of the direction of travel of the light. Furthermore, the cavity device (CH) has a partition wall (80) that is arranged between the inner housing (50) and the outer housing (70), is fixed to the inner housing (50) and the outer housing (70).

Description

Technical Field

[0001] This disclosure relates to methods for manufacturing cavity devices and electronic devices. Background Technology

[0002] In recent years, with the miniaturization and high integration of semiconductor integrated circuits, there has been a demand for higher resolution in semiconductor exposure equipment. Therefore, the use of shorter wavelengths of light emitted from exposure light sources has been developed. For example, as gas laser devices for exposure, there are KrF excimer lasers that use lasers with an output wavelength of approximately 248 nm, and ArF excimer lasers that use lasers with an output wavelength of approximately 193 nm.

[0003] The naturally oscillating light from KrF and ArF excimer lasers has a relatively wide spectral linewidth, approximately 350 pm to 400 pm. Therefore, when using projection lenses made of materials that allow ultraviolet light to pass through KrF and ArF lasers, chromatic aberration sometimes occurs. As a result, resolution may be reduced. Therefore, it is necessary to narrow the spectral linewidth of the laser output from the gas laser device to a level that eliminates chromatic aberration. Thus, in the laser resonator of a gas laser device, a line-narrowing module (LNM) containing narrowing elements (etalon, grating, etc.) is sometimes included to narrow the spectral linewidth. Hereinafter, gas laser devices with narrowed spectral linewidths will be referred to as narrow-bandgap gas laser devices.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2002-176220 Summary of the Invention

[0007] One aspect of the cavity device disclosed herein may include: an inner housing having a passage through which light generated by the excitation of a laser gas passes within the interior space of the inner housing; an outer housing surrounding at least a portion of the inner housing from the side of the direction of light travel; and a partition wall disposed between the inner and outer housings on the side and fixed to the inner and outer housings.

[0008] One aspect of the present disclosure discloses a method for manufacturing an electronic device by generating a laser using a gas laser device having a cavity, outputting the laser to an exposure device, and exposing the laser on a photosensitive substrate within the exposure device to manufacture the electronic device. The cavity device has: an inner housing having a passage through which light generated by the excitation of a laser gas passes in the internal space of the inner housing; an outer housing surrounding at least a portion of the inner housing from the side of the direction of light travel; and a partition wall disposed between the inner housing and the outer housing and fixed to the inner housing and the outer housing. Attached Figure Description

[0009] Hereinafter, several embodiments of the present disclosure will be described as simple examples with reference to the accompanying drawings.

[0010] Figure 1 This is a schematic diagram illustrating a general structural example of an electronic device manufacturing apparatus.

[0011] Figure 2 This is a schematic diagram showing the overall general structure of a comparative example gas laser device.

[0012] Figure 3 yes Figure 2 The cavity device shown is a cross-sectional view perpendicular to the direction of laser travel.

[0013] Figure 4 This is a schematic diagram illustrating a general structural example of the gas laser device according to an embodiment.

[0014] Figure 5 This is a perspective view showing the outer casing surrounding the inner casing and the temperature regulator.

[0015] Figure 6 yes Figure 4 The cavity device shown is a cross-sectional view perpendicular to the direction of laser travel.

[0016] Figure 7 This is a perspective view showing the outer main body portion surrounding the inner shell and partition wall.

[0017] Figure 8 This is a diagram showing the positional relationship between the cooling fins and the partition wall. Detailed Implementation

[0018] 1. Description of the electronic device manufacturing apparatus used in the exposure process of electronic devices

[0019] 2. Description of the comparative gas laser device

[0020] 2.1 Structure

[0021] 2.2 Actions

[0022] 2.3 Research Topic

[0023] 3. Description of the cavity device in the embodiment

[0024] 3.1 Structure

[0025] 3.2 Functions / Effects

[0026] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0027] The embodiments described below illustrate several examples of this disclosure and do not limit the scope of this disclosure. Furthermore, the structures and operations described in each embodiment are not necessarily all necessary for the structures and operations of this disclosure. Additionally, the same reference numerals are used to denote the same structural elements, and repeated descriptions are omitted.

[0028] 1. Description of the electronic device manufacturing apparatus used in the exposure process of electronic devices

[0029] Figure 1 This is a schematic diagram illustrating a general structural example of an electronic device manufacturing apparatus used in the exposure process of an electronic device. For example... Figure 1 As shown, the manufacturing apparatus used in the exposure process includes a gas laser device 100 and an exposure device 200. The exposure device 200 includes an illumination optics system 210 and a projection optics system 220. The illumination optics system 210 includes multiple mirrors 211, 212, and 213. The illumination optics system 210 illuminates the mask pattern on the mask stage RT using laser light incident from the gas laser device 100. The projection optics system 220 projects the laser light transmitted through the mask onto a workpiece (not shown) positioned on a workpiece stage WT. The workpiece is a photosensitive substrate such as a semiconductor wafer coated with photoresist. The exposure device 200 moves the mask stage RT and the workpiece stage WT synchronously and parallelly, thereby exposing the workpiece to laser light reflecting the mask pattern. Through this exposure process, a device pattern is transferred onto a semiconductor wafer, thereby enabling the manufacture of semiconductor devices as electronic devices.

[0030] 2. Description of the comparative gas laser device

[0031] 2.1 Structure

[0032] The gas laser device 100 of the comparative example will be described. Furthermore, the comparative examples disclosed herein are methods known only to the applicant and are not publicly known examples acknowledged by the applicant.

[0033] Figure 2This is a schematic diagram illustrating the overall general structure of the gas laser device 100 in this example. The gas laser device 100 is, for example, an ArF excimer laser device using a mixture of argon (Ar), fluorine (F2), and neon (Ne). In this case, the gas laser device 100 outputs pulsed laser light with a center wavelength of approximately 193 nm. The gas laser device 100 can also be a gas laser device other than an ArF excimer laser device, for example, a KrF excimer laser device using a mixture of krypton (Kr), F2, and Ne. In this case, the gas laser device 100 emits pulsed laser light with a center wavelength of approximately 248 nm. The mixture of Ar, F2, and Ne as the laser medium, and the mixture of Kr, F2, and Ne as the laser medium, are sometimes referred to as laser gases. Furthermore, in the mixtures used in ArF and KrF excimer laser devices, helium (He) can be used instead of Ne.

[0034] The gas laser device 100 in this example includes a housing 110, a laser oscillator 130 disposed in the internal space of the housing 110, a monitor module 150, a laser gas supply device 170, a laser gas exhaust device 180, and a laser processor 190 as its main structures.

[0035] The laser oscillator 130 includes a cavity device CH, a charger 141, a pulse power module 143, a rear mirror 145, and an output coupling mirror 147 as its main structures.

[0036] exist Figure 2 The image shows the internal structure of the cavity device CH as viewed from a direction approximately perpendicular to the direction of laser travel. Furthermore, Figure 3 yes Figure 2 The cavity device CH shown is a cross-sectional view perpendicular to the direction of laser travel. The cavity device CH has a housing 30, windows 31a and 31b, electrodes 32a and 32b, insulation part 33, electrode holder part 36, guides 39A, 39B and 39C, dielectric tube 42, inner electrode 43, outer electrode 44, crossflow fan 46, heat exchanger 47 and pressure sensor 48 as its main structures.

[0037] like Figure 2 As shown, the housing 30 includes an internal space where light is generated by the excitation of the aforementioned laser gas. The laser gas is supplied to the internal space of the housing 30 from the laser gas supply device 170 via piping. The light generated by the excitation of the laser gas travels toward windows 31a and 31b.

[0038] Window 31a is located at one end of the laser's direction of travel within the housing 30, and window 31b is located at the other end of the laser's direction of travel within the housing 30. Windows 31a and 31b are tilted at a Brewster angle relative to the laser's direction of travel to suppress the reflection of P-polarized laser light. Window 31a is embedded in a hole in the housing 30, and window 31b is embedded in a hole on the opposite side of the hole to the hole on the side of window 31a.

[0039] Electrodes 32a and 32b are positioned along the direction of laser travel, and are arranged opposite each other within the internal space of housing 30. The space between electrodes 32a and 32b in housing 30 is enclosed by windows 31a and 31b. Electrodes 32a and 32b are the main discharge electrodes used to excite the laser medium via glow discharge. In this example, electrode 32a is the cathode, and electrode 32b is the anode.

[0040] like Figure 3 As shown, electrode 32a is supported by insulating portion 33. Insulating portion 33 blocks the opening continuous with housing 30. Insulating portion 33 contains an insulator. Examples of insulators include alumina ceramic, which has low reactivity with F2 gas. The width of the cross-section of the portion of insulating portion 33 supporting electrode 32a narrows towards electrode 32b, which faces electrode 32a. Thus, insulating portion 33 guides the laser gas in such a way that the laser gas within housing 30 flows between electrodes 32a and 32b from the side of crossflow fan 46, assisted by airflow from crossflow fan 46. Figure 3 In the diagram, thick arrows indicate the flow of laser gas within the internal space of the housing 30. The laser gas circulates in the following sequence: crossflow fan 46, between electrodes 32a and 32b, heat exchanger 47, and back to crossflow fan 46. Furthermore, a feedthrough hole 34, composed of conductive components, is embedded in the insulating portion 33. The feedthrough hole 34 applies the voltage supplied from the pulse power module 143 to electrode 32a.

[0041] Electrode 32b is supported by and electrically connected to electrode holder 36. Electrode holder 36 is electrically connected to housing 30 via wiring 37. Guides 39A, 39B, and 39C are provided on electrode holder 36. The materials of guides 39A, 39B, and 39C are, for example, porous nickel metal with low reactivity with F2 gas. Electrode 32b is clamped and fixed to electrode holder 36 by guides 39A and 39B.

[0042] The dielectric tube 42, inner electrode 43, and outer electrode 44 are arranged along the laser's travel direction. The dielectric tube 42 is, for example, cylindrical. The dielectric tube 42 is made of a dielectric material such as alumina. The inner electrode 43 is rod-shaped and is arranged along the dielectric tube 42 within a through-hole. Figure 2 As shown, fixed tubes 42a and 42b are connected to both ends of the dielectric tube 42. A wiring (not shown) connected to one end of the inner electrode 43 is disposed within a through-hole of one fixed tube 42a. Similarly, a wiring (not shown) connected to the other end of the inner electrode 43 is disposed within a through-hole of the other fixed tube 42b. These wirings are connected to a feedthrough 34. Therefore, the feedthrough 34, as described above, applies the voltage supplied from the pulse power module 143 to the inner electrode 43.

[0043] One end of the external electrode 44 contacts a portion of the outer peripheral surface of the dielectric tube 42. Furthermore, the other end of the external electrode 44 is electrically connected to the electrode holder portion 36. Therefore, the external electrode 44 is electrically connected to the electrode 32b via the electrode holder portion 36, and is electrically connected to the housing 30 via the electrode holder portion 36 and the wiring 37. The external electrode 44 is bent between one end and the other end, with the bent portion bending in an in-plane direction perpendicular to the length direction of the dielectric tube 42. Furthermore, through bending, one end of the external electrode 44 contacts the outer peripheral surface of the dielectric tube 42 in a manner that presses against the outer peripheral surface of the dielectric tube 42. The external electrode 44 is, for example, made of brass.

[0044] A threaded hole (not shown) is provided at the other end of the outer electrode 44, and the outer electrode 44 is fixed to the guide 39B by a screw 45 screwed into the threaded hole. In this state, one end of the outer electrode 44 is pressed against and in contact with the outer peripheral surface of the dielectric tube 42. The portion of the outer peripheral surface of the dielectric tube 42 that is substantially opposite to the contact portion of one end of the outer electrode 44 is in contact with the guide 39C. Therefore, even when the outer electrode 44 presses against the dielectric tube 42, the dielectric tube 42 is supported by the guide 39C.

[0045] Inner electrode 43 and outer electrode 44 are positioned opposite each other across dielectric tube 42. By applying a high voltage to inner electrode 43 and outer electrode 44 from pulse power module 143, corona discharge is generated near dielectric tube 42 and outer electrode 44. This corona discharge assists the glow discharge generated between electrodes 32a and 32b. Therefore, inner electrode 43 and outer electrode 44 are pre-ionization electrodes that assist the glow discharge caused by electrodes 32a and 32b.

[0046] A crossflow fan 46 is disposed within the internal space of the housing 30 on the side opposite to the electrode 32b, with reference to the electrode holder 36. The space within the housing 30 where the crossflow fan 46 is disposed communicates with the space between the electrodes 32a and 32b. Therefore, when the crossflow fan 46 rotates, the laser gas sealed within the internal space of the housing 30 is circulated... Figure 3The arrows, drawn in medium-thickness, indicate circulation in a specified direction. A crossflow fan 46 is connected to a motor 46a disposed outside the housing 30. The crossflow fan 46 rotates when the motor 46a rotates. The start-up, shutdown, and rotational speed of the motor 46a are regulated by the laser processor 190. Therefore, by controlling the motor 46a, the laser processor 190 can regulate the circulation speed of the laser gas circulating within the interior space of the housing 30.

[0047] A heat exchanger 47 is disposed next to the crossflow fan 46. At least a portion of the laser gas circulated by the airflow from the crossflow fan 46 passes through the heat exchanger 47, through which the temperature of the laser gas is regulated.

[0048] return Figure 2 Continuing with the description of the gas laser device 100 in this example, the charger 141 is a DC power supply device that charges a capacitor (not shown) disposed in the pulse power module 143 with a specified voltage. The charger 141 is disposed outside the housing 30 and connected to the pulse power module 143. The pulse power module 143 includes a switch 143a controlled by the laser processor 190. When the switch 143a changes from open to closed under the control of the laser processor 190, the pulse power module 143 boosts the voltage applied from the charger 141 to generate a pulsed high voltage, which is applied to the electrodes 32a and 32b. When the high voltage is applied, the insulation between the electrodes 32a and 32b is broken down, resulting in a discharge. The energy of this discharge excites the laser medium inside the housing 30 to transition to a higher energy level. Then, when the excited laser medium transitions to a lower energy level, it emits light corresponding to the energy difference. The emitted light travels towards the windows 31a and 31b.

[0049] The rear mirror 145 is opposite to window 31a, and the output coupling mirror 147 is opposite to window 31b. A high-reflectivity film is coated on the rear mirror 145, and a partial-reflectivity film is coated on the output coupling mirror 147. The rear mirror 145 causes the laser emitted from window 31a to be reflected back to the housing 30 with high reflectivity. The output coupling mirror 147 allows a portion of the laser emitted from window 31b to pass through, while reflecting the remaining portion back to the interior space of the housing 30 via window 31b. The output coupling mirror 147 is, for example, a component with a dielectric multilayer film formed on a calcium fluoride substrate.

[0050] Therefore, a Fabry-Perot type laser resonator is constructed using the rear mirror 145 and the output coupling mirror 147, with the housing 30 positioned in the optical path of the laser resonator. The laser emitted from the housing 30 reciprocates between the rear mirror 145 and the output coupling mirror 147. The reciprocating laser is amplified each time it passes through the laser gain space between electrodes 32a and 32b. A portion of the amplified light is transmitted as a pulsed laser through the output coupling mirror 147.

[0051] The rear mirror 145 is fixed to the interior space of the housing 145a, which is connected to one end of the housing 30, via a damper (not shown). Furthermore, the output coupling mirror 147 is fixed to the interior space of the optical path tube 147a, which is connected to the other end of the housing 30, via a damper (not shown).

[0052] The monitor module 150 is configured in the optical path of the pulsed laser transmitted through the output coupling mirror 147. The monitor module 150 comprises a housing 151, a beam splitter 152, a condenser lens 153, and a photosensitive sensor 154 as its main structures. An opening is continuous with the housing 151, and an optical path tube 147a is connected to surround the opening. Therefore, the internal space of the housing 151 communicates with the internal space of the optical path tube 147a through this opening. The beam splitter 152, the condenser lens 153, and the photosensitive sensor 154 are disposed within the internal space of the housing 151.

[0053] Beam splitter 152 allows the pulsed laser light passing through output coupling mirror 147 to pass through exit window 161 with high transmittance, and reflects a portion of the pulsed laser light towards condenser lens 153. Condenser lens 153 focuses the pulsed laser light onto the light-receiving surface of optical sensor 154. Optical sensor 154 measures the measured pulse energy E of the pulsed laser light incident on the light-receiving surface. Optical sensor 154 is electrically connected to laser processor 190 and outputs a signal representing the measured pulse energy E to laser processor 190.

[0054] The opening is continuous with the side of the housing 151 of the monitor module 150 opposite to the side connected to the optical path tube 147a, and the optical path tube 161a is connected to the opening in a manner that surrounds the opening. Therefore, the internal space of the housing 151 and the internal space of the optical path tube 161a are in communication with each other. In addition, the optical path tube 161a is connected to the housing 110. An exit window 161 is provided in the housing 110 at a position surrounded by the optical path tube 161a. Light passing through the beam splitter 152 of the monitor module 150 is emitted from the exit window 161 to the exposure device 200 outside the housing 110.

[0055] The internal spaces of optical path tubes 147a and 161a, and housings 145a and 151 are filled with purge gas. The purge gas contains inert gases such as high-purity nitrogen with few impurities, including oxygen. The purge gas is supplied to the internal spaces of optical path tubes 147a and 161a, and housings 145a and 151 from a purge gas supply source (not shown) located outside housing 110 through piping (not shown).

[0056] Pressure sensor 48 measures the pressure inside the housing 30. Pressure sensor 48 is electrically connected to laser processor 190 and outputs a signal indicating the measured pressure to laser processor 190.

[0057] A laser gas supply device 170 receives laser gas from a laser gas supply source (not shown) located outside the housing 110 via piping. The laser gas supply device 170 is equipped with valves (not shown) and flow regulating valves, and is connected to other piping connected to the housing 30. Based on a control signal from the laser processor 190, the laser gas supply device 170 mixes multiple gases in a desired composition ratio to form the laser gas, and supplies this laser gas to the interior space of the housing 30 via the other piping.

[0058] The laser gas exhaust device 180 is connected to a piping system that is connected to the housing 30. The laser gas exhaust device 180 includes an exhaust pump (not shown), which discharges gas from the interior space of the housing 30 into the interior space of the housing 110 via the piping system. At this time, the laser gas exhaust device 180 adjusts the exhaust volume and other parameters according to a control signal from the laser processor 190, and performs prescribed treatment on the gas discharged from the interior space of the housing 30.

[0059] In addition, an exhaust pipe 111 is provided in the housing 110. Gas is discharged to the outside of the housing 110 from the exhaust pipe 111. This gas is gas discharged from the internal space of the housing 30 to the internal space of the housing 110 through the laser gas exhaust device 180, and gas discharged from the optical path tubes 147a, 161a, etc. (not shown) to the internal space of the housing 110.

[0060] The laser processor 190 disclosed herein is a processing device comprising a storage device storing a control program and a CPU executing the control program. The laser processor 190 is specifically configured or programmed to perform the various processes contained herein. Furthermore, the laser processor 190 controls the gas laser device 100 as a whole. Additionally, the laser processor 190 is electrically connected to the exposure processor 290 of the exposure apparatus 200, and transmits and receives various signals with and from the exposure processor 290.

[0061] 2.2 Actions

[0062] Next, the operation of the comparative example gas laser device 100 will be explained.

[0063] Before the gas laser device 100 emits a pulsed laser, purge gas is supplied from a purge gas supply source (not shown) to fill the internal spaces of the optical path tubes 147a and 161a, and the internal spaces of the housings 145a and 151 with purge gas. Additionally, laser gas is supplied from the laser gas supply device 170 to the internal space of the housing 30. After the laser gas is supplied, the laser processor 190 controls the motor 46a to rotate the crossflow fan 46. The rotation of the crossflow fan 46 circulates the laser gas within the internal space of the housing 30.

[0064] When the gas laser device 100 emits pulsed laser light, the laser processor 190 receives a signal representing the target pulse energy Et and a light emission trigger signal from the exposure processor 290. The target pulse energy Et is the target value of the pulse energy used in the exposure process. The laser processor 190 sets a predetermined charging voltage Vhv to the charger 141 so that the pulse energy becomes the target pulse energy Et, and the laser processor 190 synchronously turns on the switch 143a with the light emission trigger signal. As a result, the pulse power module 143 generates a pulsed high voltage based on the electrical energy held by the charger 141, and applies a high voltage between electrodes 32a and 32b and between the inner electrode 43 and the outer electrode 44. However, the timing of applying a high voltage between the inner electrode 43 and the outer electrode 44 is slightly earlier than the timing of applying a high voltage between electrodes 32a and 32b. After applying a high voltage between the inner electrode 43 and the outer electrode 44, a corona discharge is generated near the dielectric tube 42, emitting ultraviolet light. Furthermore, after irradiating the laser gas between electrodes 32a and 32b with ultraviolet light, the laser gas between electrodes 32a and 32b is pre-ionized. After pre-ionization, applying a high voltage between electrodes 32a and 32b causes the insulation between electrodes 32a and 32b to break down, resulting in a discharge. This discharge generates acoustic waves, which are absorbed by guides 39A, 39B, and 39C. This absorption suppresses the reflection of ultrasonic waves at guides 39A, 39B, and 39C, thus suppressing the propagation of acoustic waves towards the area between electrodes 32a and 32b. This suppresses unstable discharges and prevents a decrease in the energy stability of the light emitted from the gas laser device 100.

[0065] Furthermore, during the discharge as described above, the energy from the discharge excites the laser medium contained in the laser gas between electrodes 32a and 32b, causing it to emit spontaneously emitted light upon returning to its ground state. A portion of this light is ultraviolet and passes through window 31a. The transmitted light is reflected at rear mirror 145. The light reflected at rear mirror 145 propagates again from window 31a into the interior space of housing 30. The laser medium in the excited state undergoes stimulated emission due to the light propagating into the interior space of housing 30, amplifying the light. The light then travels through window 31b towards output coupling mirror 147. A portion of the light passes through output coupling mirror 147, while the remainder is reflected by output coupling mirror 147 and propagates through window 31b into the interior space of housing 30. The light propagating into the interior space of housing 30 travels towards rear mirror 145 as described above. Thus, light of a predetermined wavelength oscillates between rear mirror 145 and output coupling mirror 147. Each time the light passes through the discharge space within housing 30, it is amplified, generating laser oscillations. Furthermore, a portion of the laser, as a pulsed laser, travels through the output coupling mirror 147 toward the beam splitter 152.

[0066] A portion of the pulsed laser traveling toward beam splitter 152 is reflected at beam splitter 152. The reflected pulsed laser is received at optical sensor 154, which measures the pulse energy E of the received pulsed laser. Optical sensor 154 outputs a signal representing the measured pulse energy E to laser processor 190. Laser processor 190 performs feedback control on the charging voltage Vhv of charger 141 to ensure that the difference ΔE between the pulse energy E and the target pulse energy Et is within an acceptable range. When the difference ΔE is within the acceptable range, the pulsed laser passes through beam splitter 152 and exit window 161 and enters exposure apparatus 200. This pulsed laser is an ArF laser, which is ultraviolet light with a center wavelength of approximately 193 nm.

[0067] The pressure inside the housing 30 is measured by a pressure sensor 48, and the pressure signal from the pressure sensor 48 is input to the laser processor 190. When the charging voltage Vhv is higher than the maximum allowable value, the laser processor 190 controls the laser gas supply device 170 based on the signal from the pressure sensor 48 to supply laser gas to the inside of the housing 30 until the pressure inside the housing 30 reaches a predetermined pressure. Furthermore, when the charging voltage Vhv is lower than the minimum allowable value, the laser processor 190 controls the laser gas exhaust device 180 based on this signal to exhaust laser gas from the inside of the housing 30 until the pressure reaches a predetermined pressure.

[0068] 2.3 Research Topic

[0069] In the cavity device CH of the comparative example, when light is generated by excitation by laser gas, the temperature inside the housing 30 sometimes rises. When the temperature rises, the temperature distribution within this internal space sometimes deviates. Furthermore, when laser gas is supplied from the laser gas supply device 170 to the internal space of the housing 30, the pressure within this internal space rises. Due to the thermal expansion of the housing 30 caused by the temperature rise, the difference in thermal expansion within the internal space of the housing 30 caused by the temperature distribution deviation, and the pressure rise, the housing 30 sometimes deforms. When the housing 30 deforms, the travel direction of the laser emitted from the housing 30 sometimes changes relative to the intended travel direction. Due to this change, the travel direction of the laser emitted from the gas laser device 100 toward the exposure device 200 also sometimes changes relative to the intended travel direction. Therefore, there is concern about a decrease in the reliability of the gas laser device 100.

[0070] Therefore, in the following embodiments, a cavity device CH capable of suppressing the decrease in reliability of the gas laser device 100 is illustrated.

[0071] 3. Description of the cavity device in the embodiment

[0072] Next, the cavity device CH of the embodiment will be described. Furthermore, structures identical to those described above will be labeled with the same reference numerals, and repeated descriptions will be omitted unless specifically stated otherwise. Additionally, in some of the accompanying drawings, parts of components may be omitted or simplified for ease of observation.

[0073] 3.1 Structure

[0074] Figure 4 This is a schematic diagram showing a general structural example of the gas laser device 100 according to this embodiment. Figure 4 The image shows the internal structure of the cavity device CH as viewed from a direction approximately perpendicular to the direction of laser travel. Figure 5 This is a perspective view showing the outer housing 70 surrounding the inner housing 50 and the temperature regulator 93 in the cavity device CH. Figure 6 yes Figure 4 The cavity device CH shown is a cross-sectional view perpendicular to the direction of laser travel. Figure 6 In the example, similar to the comparative example, the flow of laser gas is shown using thick arrows.

[0075] In the cavity device CH of this embodiment, the structure of the housing of the cavity device CH is different from the structure of the housing 30 in the comparative example. The cavity device CH of this embodiment has a cylindrical inner housing 50, an outer housing 70 that surrounds the inner housing 50 from the outside, a partition wall 80 that is disposed on the side of the laser travel direction to form a gap between the inner housing 50 and the outer housing 70, a temperature sensor 91, and a temperature regulator 93 as its main structures.

[0076] Similar to the housing 30 of the comparative example, the inner housing 50 includes an internal space that generates light through excitation by laser gas. Also similar to the internal space of the housing 30 of the comparative example, this internal space houses electrodes 32a and 32b, an insulating portion 33, an electrode holder portion 36, guides 39A, 39B, and 39C, a dielectric tube 42, an inner electrode 43, an outer electrode 44, a crossflow fan 46, a heat exchanger 47, and a pressure sensor 48. Pipings for the laser gas supply device 170 and the laser gas exhaust device 180 penetrate the outer housing 70 and communicate with the internal space of the inner housing 50. The length direction of the inner housing 50 is along the direction of laser travel within its internal space, and the laser passes through openings 50a and 50b at both ends of the cylindrical inner housing 50. This inner housing 50 surrounds the laser traveling within its internal space.

[0077] Figure 7 This is a perspective view showing the outer main body 71 of the outer shell 70 that surrounds the inner shell 50 and the partition wall 80. Figure 7In the diagram, the portion of the inner housing 50 and the partition wall 80 surrounded by the outer main body 71 is shown using dashed lines.

[0078] like Figure 6 and Figure 7 As shown, the inner housing 50 comprises a rectangular base plate 51a that is longer in the longitudinal direction of the inner housing 50, and a pair of semi-circular curved panels 51b and 51c as its main structure. Each curved panel 51b and 51c is of the same size. Viewed along the longitudinal direction of the inner housing 50, the curved panels 51b and 51c are arranged symmetrically about the base plate 51a, and are curved in a manner that bulges outwards from each other. In the width direction of the base plate 51a, the outer peripheral surface of one end of the curved panel 51b is fixed to the inner surface of one end of the base plate 51a by brazing, and the outer peripheral surface of one end of the curved panel 51c is fixed to the inner surface of the other end of the base plate 51a by brazing. During brazing, the curved panels 51b and 51c are brazed together at their contact portions with the base plate 51a. This suppresses the leakage of laser gas from this fixed portion to the outside of the inner housing 50. Furthermore, a portion of the other end of each curved panel 51b and 51c is bent outward toward the inner housing 50 in a direction substantially perpendicular to the base plate 51a. The other ends of each bent panel are fixed by brazing as described above and are provided with a frame-shaped protrusion 53. The frame-shaped protrusion 53 is a longer rectangular shape in the longitudinal direction of the inner housing 50, and an opening 50c is provided on the inner side of the frame-shaped protrusion 53. The opening 50c is a longer rectangular shape in the longitudinal direction of the inner housing 50 and is blocked by the insulating portion 33. Further outward in the longitudinal direction of the inner housing 50 than the protrusion 53, a remaining portion of the other end of each bent curved panel 51b and 51c is bent in a manner facing the base plate 51a, and the remaining portion is fixed to each other by brazing.

[0079] The thickness of the base plate 51a is greater than the thickness of the curved panels 51b and 51c in the inner housing 50, excluding the base plate 51a. For example, the thickness of the base plate 51a is 5 mm or more and 7 mm or less, while the thickness of the curved panels 51b and 51c is 1 mm or more and 3 mm or less. Thus, the thickness of the inner housing 50 is 1 mm or more and 7 mm or less. When the flat base plate 51a is thicker than the curved panels 51b and 51c, the strength of the base plate 51a is increased compared to the case where the thickness of the base plate 51a is the same as that of the curved panels 51b and 51c. Furthermore, when the base plate 51a is flat, the volume of the cavity device CH is reduced compared to the case where the base plate 51a is a curved panel that bulges outward from the central axis of the inner housing 50. When the volume is reduced, the consumption of laser gas from the laser gas supply device 170 is reduced, and the gas laser device 100 as a whole becomes smaller. The inner shell 50 can be made of, for example, a nickel alloy, ferritic stainless steel, or duplex stainless steel. For instance, the nickel alloy could be Monel, which has a coefficient of linear expansion of 13.9 × 10⁻⁶. -6 / ℃. For example, ferritic stainless steel is SUS430, and the coefficient of linear expansion of SUS430 is 10.4 × 10⁻⁶. -6 / ℃. Furthermore, for example, duplex stainless steel is SUS329J4L, which has a coefficient of linear expansion of 13.0 × 10⁻⁶. -6 / ℃.

[0080] like Figure 6 As shown, cooling fins 57 are fixed to a portion of the inner circumferential surface of the inner housing 50 by brazing. During brazing, the cooling fins 57 are brazed integrally at the contact portion with the inner circumferential surface of the inner housing 50. Figure 6 The diagram shows an example where cooling fins 57 are fixed to the surface of the base plate 51a and the inner circumferential surface of the curved plate 51b. In the direction of travel of the laser gas circulating in the internal space of the inner housing 50 via the crossflow fan 46, the cooling fins 57 are positioned downstream of the space between electrodes 32a and 32b. The cooling fins 57 are positioned laterally to the laser's path within the internal space of the inner housing 50, without obstructing the laser. Heat within the internal space of the inner housing 50 is released to the outside of the inner housing 50 via the cooling fins 57. The cooling fins 57... Figure 6 and the following Figure 8 Illustrations are omitted from the accompanying drawings other than those shown.

[0081] like Figure 5 , Figure 6 and Figure 7 As shown, the outer housing 70 surrounds the inner housing 50 from the side, front, and rear of the laser's direction of travel. This outer housing 70 includes an outer main body 71, a cover plate 73, a front panel 75, and a rear panel 77 as its main structures.

[0082] The outer main body 71 is a plate that surrounds the inner shell 50 from the side and includes an opening 70c on the side. The cross-section of this outer main body 71 is, for example, U-shaped. The outer main body 71 is disposed facing the bottom plate 51a, curved panels 51b, 51c, and protrusion 53 of the inner shell 50, respectively. The outer main body 71 has approximately the same length as the inner shell 50, and its length direction is along the length direction of the inner shell 50.

[0083] A cover plate 73 is disposed at both ends of the outer main body portion 71 and at the openings 70c at both ends, covering the openings 70c side of the outer main body portion 71. The openings 73c into which the protrusions 53 of the inner housing 50 are inserted are continuous with the cover plate 73. Furthermore, a groove continuous with the upper surface of the cover plate 73 is also continuous with the cover plate 73. The groove is provided around the openings 73c and is a rectangular shape that is longer in the longitudinal direction of the inner housing 50. A sealing member 79 is disposed in the groove to seal between the cover plate 73 and the insulating portion 33. The sealing member 79 is, for example, a metal seal.

[0084] Furthermore, the cover plate 73 includes a protrusion 73a that protrudes outward from the side of the outer main body portion 71 in a direction orthogonal to the length direction of the outer main body portion 71. This side is the surface in the outer main body portion 71 that faces the curved panels 51b and 51c in the width direction of the bottom plate 51a of the inner housing 50. The protrusions 73a are respectively provided at both ends in the orthogonal direction of the cover plate 73. Each protrusion 73a is bent relative to the side of the cover plate 73 facing the outer main body portion 71 in a manner that surrounds the side. In this case, the bending angle of the protrusion 73a is, for example, 25° or more and 35° or less. Furthermore, the length of the protrusion 73a is, for example, 100 mm or more and 150 mm or less. This length is the length from the bent portion of the protrusion 73a to the end furthest from the bent portion, not the length between the side of the outer main body portion 71 and that end. Figure 6 The image shows an example where the bend is located on the side of the side surface; however, it can also be located on the edge of the side surface.

[0085] Furthermore, the in-plane direction of the planar area of ​​the cover plate 73, excluding the protrusion 73a, is parallel to the in-plane direction of the base plate 51a. The protrusion 73a may also protrude further outward than the side of the outer main body 71 along the in-plane direction. Alternatively, the protrusion 73a may be bent to the side opposite to the side of the outer main body 71. Regarding the length of the protrusion 73a, it is shortest when bent towards the side of the outer main body 71, and successively longer when bent towards the side of the outer main body 71, bent towards the side opposite to the side of the outer main body 71, and protruding along the in-plane direction.

[0086] like Figure 5 As shown, the front panel 75 has an opening 50a and its periphery on one end of the inner housing 50, and an opening and its periphery on one end of the outer housing 70, arranged along the length of the inner housing 50 and the outer main body 71. The opening 75a is continuous with the front panel 75. The opening 75a is approximately the same size and shape as the opening 50a of the inner housing 50, and overlaps with the opening 50a when the front panel 75 is mounted on one end of the inner housing 50 and one end of the outer main body 71. An output-side retainer (not shown) for holding the output coupling mirror 147 is mounted on the front panel 75. The output-side retainer is mounted on the front panel 75 such that the output coupling mirror 147 faces the opening 50a.

[0087] The rear panel 77 is configured along the length of the inner housing 50 and the outer main body 71, with an opening 50b and its periphery on the other end side of the inner housing 50, and an opening and its periphery on the other end side of the outer housing 70. An opening (not shown) is continuous with the rear panel 77. This opening is approximately the same size and shape as the opening 50b of the inner housing 50, and overlaps with the opening 50b when the rear panel 77 is mounted on the other end side of both the inner housing 50 and the outer main body 71. A rear retainer (not shown) for holding the rear mirror 145 is mounted on the rear panel 77. The rear retainer is mounted on the rear panel 77 such that the rear mirror 145 faces the opening 50b of the inner housing 50. Therefore, in the cavity device CH of this embodiment, the housing 145a is not required.

[0088] A partition wall 80 is provided in the outer housing 70, therefore, the strength of the outer housing 70 can be lower than that of the inner housing 50. Therefore, the thickness of each of the outer main body 71, cover plate 73, front panel 75, and rear panel 77 can be thinner than that of the inner housing 50. When each plate is thinner, the weight of the cavity device CH is reduced compared to when each plate is the same as or thicker than that of the inner housing 50. The thickness of each of the outer main body 71, cover plate 73, front panel 75, and rear panel 77 is, for example, 1 mm or more and 3 mm or less. Similar to the inner housing 50, the material of the outer main body 71, cover plate 73, front panel 75, and rear panel 77 can be, for example, a nickel alloy.

[0089] like Figure 6 and Figure 7As shown, there are multiple partition walls 80, each of which serves as a support member for the inner housing 50, the outer main body 71, and the cover plate 73 except for the protrusion 73a. The partition walls 80 are fixed to the outer peripheral surface of the inner housing 50 and the inner peripheral surface of the outer housing 70 by brazing. During brazing, the contact portion of the partition wall 80 that contacts the outer peripheral surface of the inner housing 50 and the contact portion that contacts the inner peripheral surface of the outer housing 70 are brazed together. The inner peripheral surface of the outer housing 70 is the inner peripheral surface of the outer main body 71 and the back surface of the cover plate 73 except for the protrusion 73a.

[0090] Each partition wall 80 is arranged side-by-side at predetermined intervals along the length of the inner housing 50, with its in-plane direction approximately perpendicular to the length direction of the inner housing 50. Therefore, the surface of one partition wall 80 faces the back surface of the adjacent partition wall 80, and the adjacent partition walls 80 are arranged with a gap between them. The partition wall 80 is a wall that separates the gap between the inner housing 50 and the outer main body 71 in a direction orthogonal to the length direction of the inner housing 50, and also separates this gap back and forth along the length direction of the inner housing 50. Furthermore, gaps are also provided between the front panel 75 and the partition wall 80 adjacent to the front panel 75, and between the rear panel 77 and the partition wall 80 adjacent to the rear panel 77. Figure 7 The example shown has 11 partition walls 80, but at least one partition wall 80 is required.

[0091] Figure 8 This is a diagram showing the positional relationship between the cooling fins 57 and the partition wall 80. (See diagram below.) Figure 8 As shown, a plurality of cooling fins 57 are arranged on the inner circumferential surface of the inner housing 50. Similar to the partition wall 80, each cooling fin 57 is arranged side-by-side at predetermined intervals along the length of the inner housing 50, with its in-plane direction approximately perpendicular to the length direction of the inner housing 50. Furthermore, the partition wall 80 and the cooling fins 57 are arranged alternately along the length direction of the inner housing 50. Preferably, the cooling fins 57 are arranged approximately at the midpoint between adjacent partition walls 80 along the length direction of the inner housing 50. Therefore, the length between adjacent partition walls 80 is approximately the same as the length between adjacent cooling fins 57. Alternatively, if the lengths between them are the same, the cooling fins 57 may not be arranged approximately at the midpoint between adjacent partition walls 80. Figure 8 The diagram shows an example with multiple cooling fins 57, but only one cooling fin 57 may be configured, or none may be configured. Furthermore, multiple cooling fins 57 may also be configured circumferentially along the inner housing 50. In this case, adjacent cooling fins 57 may be configured separately from each other or close to each other.

[0092] Temperature sensor 91 measures the temperature of the internal space of the inner housing 50. Figure 4 and Figure 5 The temperature regulator 93 shown is a cooler that supplies cooling medium to the gap between the inner housing 50 and the outer main body 71 via a pump (not shown) of the temperature regulator 93, thereby cooling the inner housing 50. The temperature sensor 91 and the temperature regulator 93 are electrically connected to the laser processor 190. The temperature sensor 91 outputs a signal indicating the temperature of the internal space of the inner housing 50 to the laser processor 190, which then outputs a signal indicating the temperature of the cooling medium to the temperature regulator 93 based on this signal. The cooling medium is a liquid, but it can also be a gas. The temperature regulator 93 adjusts the temperature of the cooling medium based on the signal from the laser processor 190. Preferably, the set temperature of the cooling medium is, for example, above 20°C and below 70°C, and the temperature range of the cooling medium flowing in the flow path is the set temperature ±3°C.

[0093] Temperature regulator 93 is connected to piping 93a and piping 93b. Pipe 93a is connected to an inlet 75d located on the front panel 75, and piping 93b is connected to an outlet 77d located on the rear panel 77. Outlet 77d is located at... Figure 5 The image is obscured and not shown, but... Figure 8 The diagram shows the temperature regulator 93 circulating the cooling medium in the following order: temperature regulator 93, piping 93a, the gap between the inner housing 50 and the outer main body 71, piping 93b, and temperature regulator 93. Alternatively, the temperature regulator 93 can also circulate the cooling medium in the reverse order. The flow path of the cooling medium flowing in the gap between the inner housing 50 and the outer main body 71 is the gap between the front panel 75 and the adjacent partition wall 80, the gaps between adjacent partition walls 80, and the gap between the rear panel 77 and the adjacent partition wall 80. The gaps between adjacent partition walls 80 are surrounded by the partition wall 80, curved panels 51b and 51c, protrusion 53, outer main body 71, and cover plate 73.

[0094] like Figure 6 , Figure 7 and Figure 8 As shown, the cavity device CH also includes a passage 80a, which is located at the same position as the partition wall 80 in the longitudinal direction of the inner housing 50. Cooling medium flows from one of the adjacent gaps through the passage 80a to the other gap adjacent to that gap. Furthermore, in Figure 7 and Figure 8The diagram shows an example of a passage 80a being provided in an opening of a partition wall 80. Passage 80a is part of a flow path. From the front panel 75 side to the rear panel 77 side, cooling medium flows from a gap on the front panel 75 side through passage 80a to a gap on the rear panel 77 side adjacent to that gap. Viewed along the length of the inner housing 50, the passage 80a of one of the adjacent partition walls 80 is positioned so as not to overlap with the passage 80a of the other partition wall 80. Therefore, at least a portion of the passage 80a of one partition wall 80 is offset from the passage 80a of the other partition wall 80 in the circumferential direction of the inner housing 50. Furthermore, in Figure 7 and Figure 8 The following example is shown: When viewed along the length of the inner housing 50, a passage 80a of one partition wall 80 is positioned on the opposite side of a passage 80a of another partition wall 80, relative to a non-flowing area where the cooling medium does not flow in the gap. The non-flowing area is the region between the protrusions 53 of the curved panels 51b and 51c in the in-plane direction of the base plate 51a. When viewed along the length of the inner housing 50, for example, the cooling medium flows clockwise in the circumferential direction of the inner housing 50 in the gap on the front panel 75 side, and counterclockwise in the circumferential direction in the gap on the rear panel 77 side adjacent to this gap. Therefore, the cooling medium flows in opposite directions in adjacent gaps. Figure 7 The dashed arrows in the diagram illustrate the flow of the cooling medium in each gap. Figure 7 For ease of observation, one flow diagram is shown for each flow path. In the flow path, as described above, the partition wall 80 is brazed at both the contact portion that contacts the outer peripheral surface of the inner housing 50 and the contact portion that contacts the inner peripheral surface of the outer housing 70. This prevents leakage of the cooling medium from these contact portions, allowing the cooling medium to flow from one gap to another in adjacent gaps via passage 80a.

[0095] 3.2 Functions / Effects

[0096] The cavity device CH of this embodiment includes: an inner housing 50, which includes openings 50a and 50b, which are passageways for light generated by the excitation of laser gas to pass through; an outer housing 70, which surrounds the inner housing 50 from the side of the light travel direction; and a partition wall 80, which is disposed between the inner housing 50 and the outer housing 70 and is fixed to the inner housing 50 and the outer housing 70.

[0097] Within the cavity device CH, when light is generated by excitation by laser gas, the temperature inside the inner housing 50 sometimes rises. When the temperature rises, the temperature distribution within this inner housing sometimes deviates. Furthermore, when laser gas is supplied from the laser gas supply device 170 to the inner housing 50, the pressure within this inner housing increases. Due to the thermal expansion of the inner housing 50 caused by the temperature rise, the differential thermal expansion within the inner housing 50 caused by the temperature distribution deviation, and the pressure increase, the inner housing 50 is prone to deformation. However, in the cavity device CH of this embodiment, this deformation of the inner housing 50 can be suppressed by the partition wall 80 fixed to the outer peripheral surface of the inner housing 50 and the outer housing 70 to which the partition wall 80 is fixed. For example, even if the inner housing 50 is prone to expansion due to thermal expansion and pressure increase, the expansion of the inner housing 50 can be suppressed by the partition wall 80 and the outer housing 70. Furthermore, even if the inner housing 50 is to deform in a contracting manner, the contraction of the inner housing 50 can be suppressed by the partition wall 80 and the outer housing 70. When the deformation of the inner housing 50 is suppressed in this way, it is possible to suppress changes in the travel direction of the laser emitted from the inner housing 50 relative to the intended travel direction. When this change is suppressed, it is possible to suppress changes in the travel direction of the light emitted from the gas laser device 100 toward the exposure device 200 relative to the intended travel direction. Therefore, it is possible to suppress any reduction in the reliability of the gas laser device 100.

[0098] Furthermore, in the cavity device CH of this embodiment, the partition wall 80 and the outer shell 70 suppress the deformation of the inner shell 50. Therefore, compared with the state where the partition wall 80 and the outer shell 70 are not provided, the thickness of the inner shell 50 can be reduced. Therefore, even with the partition wall 80 and the outer shell 70 provided, the weight of the cavity device CH can be reduced, and the handling of the cavity device CH can be made easier. In addition, in the state where the partition wall 80 and the outer shell 70 are not provided, in order to suppress the deformation of the inner shell 50, it is necessary to increase the rigidity of the inner shell 50. In order to increase rigidity, it is necessary to increase the thickness of the inner shell 50. In the cavity device CH of this embodiment, the deformation of the inner shell 50 is suppressed by the partition wall 80 and the outer shell 70, so it is not necessary to increase the thickness of the inner shell 50. In addition, in the cavity device CH of this embodiment, the rigidity of the cavity device CH can be improved by the partition wall 80 and the outer shell 70.

[0099] Furthermore, in the cavity device CH of this embodiment, there are multiple partition walls 80. In this case, compared with the case where there is only one partition wall 80, the deformation of the inner housing 50 can be suppressed, and the rigidity of the cavity device CH can be improved.

[0100] Furthermore, in the cavity device CH of this embodiment, the cover plate 73 includes a protrusion 73a that protrudes further outward than the side of the outer main body portion 71. With the protrusion 73a provided, the rigidity of the cover plate 73 is increased by the amount of the protrusion 73a compared to the case where the protrusion 73a is not provided. Therefore, even if the inner housing 50 deforms, the cover plate 73 suppresses the deformation of the inner housing 50, and can also suppress the deformation of the cover plate 73 caused by the deformation of the inner housing 50. Furthermore, by increasing the rigidity of the cover plate 73 as described above, deformation of the cover plate 73 can be suppressed compared to the case where the protrusion 73a is not provided, and the thickness of the cover plate 73 including the protrusion 73a can be reduced. Therefore, even with the protrusion 73a provided, the weight of the cavity device CH can be reduced, and the handling of the cavity device CH becomes easier.

[0101] Furthermore, in the cavity device CH of this embodiment, the protrusion 73a is bent toward the side of the cover plate 73 facing the outer main body portion 71. In this case, compared to the case where the protrusion 73a is bent toward the side away from the outer main body portion 71, the protrusion 73a can be shortened so that the cover plate 73 has the same rigidity in all cases. Therefore, the weight of the cavity device CH can be reduced.

[0102] Furthermore, in the cavity device CH of this embodiment, cooling fins 57 are disposed on the inner circumferential surface of the inner shell 50, and heat in the internal space of the inner shell 50 is released to the outside of the outer shell 70 via the cooling fins 57, the inner shell 50, the partition wall 80, and the outer shell 70. With the cooling fins 57 disposed, the heat dissipation increases compared to the case where the cooling fins 57 are not disposed, which can suppress the temperature rise of the inner shell 50 and the deviation of the temperature distribution in the internal space of the inner shell 50, and can suppress the deformation of the inner shell 50.

[0103] Furthermore, in the cavity device CH of this embodiment, there are multiple cooling fins 57. In this case, the heat dissipation is increased compared to the case where there is only one cooling fin 57. When the heat dissipation is increased, the temperature rise of the inner shell 50 and the deviation of the temperature distribution in the internal space of the inner shell 50 can be further suppressed, and the deformation of the inner shell 50 can be further suppressed.

[0104] Furthermore, in the cavity device CH of this embodiment, the partition walls 80 and cooling fins 57 are alternately arranged along the direction of light travel. The rigidity of the inner shell 50 between adjacent partition walls 80 is reduced compared to the rigidity of the inner shell 50 at the portion where the partition walls 80 are located, due to the absence of partition walls 80. When the partition walls 80 and cooling fins 57 are alternately arranged as described above, the rigidity of the inner shell 50 between adjacent partition walls 80 is increased due to the arrangement of cooling fins 57, compared to the case where the partition walls 80 are arranged adjacent to the cooling fins 57 with the inner shell 50 in between. Therefore, deformation of the inner shell 50 can be suppressed compared to the case where the partition walls 80 are arranged adjacent to the cooling fins 57 with the inner shell 50 in between. Alternatively, the cooling fins 57 may be arranged at the same position as the partition walls 80, that is, adjacent to the partition walls 80 with the inner shell 50 in between.

[0105] Furthermore, in the cavity device CH of this embodiment, the cooling fins 57 are disposed in the middle of adjacent partition walls 80. In this case, compared to the case where the cooling fins 57 are disposed biased towards one of the adjacent partition walls 80, changes in the strength distribution of the inner shell 50 in the length direction of the inner shell 50 can be suppressed, and deformation of the inner shell 50 can be suppressed. In addition, the length between adjacent partition walls 80 may also be different from the length between adjacent cooling fins 57.

[0106] Furthermore, in the cavity device CH of this embodiment, the adjacent gap between the inner housing 50 and the outer housing 70, divided by the partition wall 80, serves as a flow path for the cooling medium. When the cooling medium flows through the gap, it comes into contact with the outer peripheral surface of the inner housing 50, directly cooling the inner housing 50. When the cooling medium cools the inner housing 50, it can suppress the temperature rise of the inner housing 50 and suppress deformation of the inner housing 50.

[0107] Furthermore, in the cavity device CH of this embodiment, the flow path is provided on the outside of the inner housing 50. In this case, compared with the case where the flow path is provided on the inside of the inner housing 50, the flow path resistance in the circulation path of the laser gas in the internal space of the inner housing 50 is reduced, and the output of the motor 46a of the crossflow fan 46 can be reduced.

[0108] Furthermore, when the cooling medium cools the inner housing 50, the heat capacity of the heat exchanger 47 can be reduced, or it may not be necessary, compared to the case where the cooling medium does not cool the inner housing 50. Therefore, the weight of the cavity device CH can be reduced. Additionally, even with the cooling fins 57, the capacity of the heat exchanger 47 can be reduced, or it may not be necessary. Furthermore, the temperature regulator 93 may not be required, and the cooling medium may not flow in the gap.

[0109] Furthermore, the cavity device CH of this embodiment includes a passage 80a, which is positioned at the same location as the partition wall 80 in the laser's travel direction. Cooling medium flows from one gap to another in adjacent gaps via passage 80a. Without passage 80a, piping would need to be connected to each gap to allow the cooling medium to flow through them. However, by providing passage 80a, piping is not required in each gap, reducing the weight of the cavity device CH. Moreover, by providing an inlet 75d in the front panel 75 and an outlet 77d in the rear panel 77, the cooling medium can circulate within the flow path as it flows through each gap.

[0110] Alternatively, passageway 80a may not be provided at each partition wall 80, but rather connected to piping in each gap, with the cooling medium flowing in each gap. When the cooling medium circulates as described above, its temperature rises due to heat from the inner shell 50 as it flows from upstream to downstream, sometimes failing to cool the inner shell 50 as intended. However, when the cooling medium flows in each gap, compared to the case of circulation as described above, temperature changes in the cooling medium can be suppressed, the inner shell 50 can be cooled, and deformation of the inner shell 50 can be suppressed.

[0111] Passage 80a may not be provided in all partition walls 80. For example, if passage 80a is not provided in the fifth partition wall 80 from the front panel 75 side, the first to fifth gaps from the front panel 75 side become one flow path, and the sixth to twelfth gaps from the front panel 75 side become different flow paths. In this case, piping can be connected to each flow path to allow the cooling medium to flow in each flow path. Alternatively, multiple passages 80a may be provided in one partition wall 80.

[0112] Furthermore, in the cavity device CH of this embodiment, when viewed along the direction of light travel, the passage 80a of one of the adjacent partition walls 80 is positioned so as not to overlap with the passage 80a of the other partition wall 80. This allows the cooling medium to flow in opposite directions within the adjacent gaps.

[0113] Furthermore, in the cavity device CH of this embodiment, the outer housing 70 includes a plate that surrounds the surface of the inner housing 50 containing the passage opening. A mirror is disposed on this plate, facing the passage opening and reflecting at least a portion of the laser beam. When the passage opening is an opening 50a, the plate is a front panel 75, and the mirror is an output coupling mirror 147. The output coupling mirror 147, facing the opening 50a, is disposed on the front panel 75 via an output-side retainer. Even though the front panel 75 is disposed within the inner housing 50, deformation of the inner housing 50 is suppressed as described above; therefore, displacement of the front panel 75 containing the output coupling mirror 147 can be suppressed. It is assumed that when the front panel 75 containing the output coupling mirror 147 shifts, the travel direction of the laser beam passing through the output coupling mirror 147 sometimes changes relative to the intended travel direction. However, when the displacement of the front panel 75 is suppressed as described above, the change in the travel direction of the laser beam passing through the output coupling mirror 147 relative to the intended travel direction can be suppressed. When this change is suppressed, it is possible to prevent the direction of light emitted from the gas laser device 100 toward the exposure device 200 from changing relative to the intended direction of travel. Therefore, it is possible to suppress the decrease in reliability of the gas laser device 100. Furthermore, when the output coupling mirror 147 is disposed on the front panel 75, the damper in the optical path tube 147a described in the comparative example gas laser device 100 is not required. Therefore, the weight of the cavity device CH can be reduced. In addition, if the housing 151 of the monitor module 150 is connected to the front panel 75, the optical path tube 147a is not required, and the weight of the cavity device CH can be reduced.

[0114] Furthermore, when the opening is 50b, the plate is the rear panel 77, and the mirror is the rear mirror 145. The rear mirror 145, facing the opening 50b, is disposed on the rear panel 77 via a rear retainer. In this case, similar to the front panel 75, displacement of the rear panel 77 containing the rear mirror 145 can be suppressed, and a decrease in the reliability of the gas laser device 100 can be prevented. Moreover, when the rear mirror 145 is disposed on the rear panel 77, the housing 145a and damper described in the comparative example gas laser device 100 are not required. Therefore, the weight of the cavity device CH can be reduced.

[0115] Furthermore, in the cavity device CH of this embodiment, an insulating portion 33 and a sealing member 79 are provided on the cover plate 73 to seal between the cover plate 73 and the insulating portion 33. In this case, compared with the case where the sealing member 79 is not provided, it is possible to suppress the intrusion of impurities such as oxygen from the outside of the outer housing 70 into the inside, and the number of laser gas replacements can be reduced. In addition, in the cavity device CH of this embodiment, the cover plate 73 is made of nickel alloy, and the sealing member 79 is a metal seal. The coefficient of linear expansion of the alumina ceramic of the insulating portion 33 is, for example, 7.2 × 10⁻⁶. -6 / ℃. Furthermore, for example, the nickel alloy is Monel alloy. Compared to Monel alloy, SUS430, and SUS329J4L, the coefficient of linear expansion of Monel alloy and alumina ceramic can be reduced, which can suppress the relative positional displacement of the insulating part 33 relative to the cover plate 73. When suppressing positional displacement, a metal seal with high sealing performance, which is prone to gas laser leakage due to positional displacement, can be used as the sealing element 79. When a metal seal is used, the reliability of the seal is further improved compared to the case where a sealing element other than a metal seal is used.

[0116] In the cavity device CH of this embodiment, the passage 80a is provided as an opening, but it is not limited to this. For example, a portion of the partition wall 80 may be configured to be separated from at least one of the inner housing 50 and the outer housing 70, and the passage 80a is a gap between this portion and at least one of the inner housing 50 and the outer housing 70. As such a passage 80a, for example, a portion of the partition wall 80 may be configured to be separated from the other end side of the curved panel 51b and the protrusion 53 on the curved panel 51b side, providing a gap between the other end side of the curved panel 51b, the protrusion 53, the partition wall 80, and the cover plate 73. Alternatively, this gap may also be provided on the curved panel 51c side. Or, the passage 80a may also be formed by a cut in the partition wall 80 and a cover plate 73 blocking the opening in the cut. The outer housing 70 may also surround at least a portion of the inner housing 50. The outer housing 70 may also surround the inner housing 50 at least from the side of the laser travel direction. The outer main body 71 may be longer or shorter than the inner shell 50. Alternatively, the cooling fins 57 may be fixed to the inner circumferential surface of the inner shell 50 by welding, and the partition wall 80 may be fixed to the outer circumferential surface of the inner shell 50 and the inner circumferential surface of the outer shell 70 by welding. The component disposed between the inner shell 50 and the outer shell 70 and fixed thereto need not be limited to the partition wall 80. This component can support the inner shell 50, the outer main body 71, and the cover plate 73 except for the protrusion 73a. For example, this component may be a rod-shaped component that supports the outer main body 71 of the inner shell 50 and the outer shell 70. There may be multiple rod-shaped components, such as spokes, extending radially from the outer circumferential surface of the inner shell 50 toward the inner circumferential surface of the outer main body 71 and the back surface of the cover plate 73 except for the protrusion 73a, with the central axis of the inner shell 50 as the reference. In addition, multiple partition walls 80 may also be arranged along the circumference of the inner shell 50. In this configuration, adjacent partition walls can be arranged separately or close to each other. Cooling fins 57 can also be disposed on the outer peripheral surface of the outer housing 70. A temperature sensor can also be installed in the flow path of the cooling medium. The temperature sensor measures the temperature of the cooling medium flowing in the flow path. The temperature sensor is electrically connected to the laser processor 190 and outputs a signal indicating the temperature of the cooling medium to the laser processor 190. The laser processor 190 can also output a signal indicating the temperature of the cooling medium to the temperature regulator 93 based on this signal and the signal from the temperature sensor 91.

[0117] The foregoing description is not a limitation but a simple illustration. Therefore, those skilled in the art will understand that modifications can be made to embodiments of this disclosure without departing from the claims. Furthermore, those skilled in the art will understand the use of embodiments of this disclosure in combination.

[0118] Unless explicitly stated otherwise, all terms used in this specification and claims should be interpreted as "non-limiting". For example, terms such as "comprising", "having", "possessing", and "comprise" should be interpreted as "excluding the presence of structural elements other than the described structural elements". Furthermore, the modifier "a" should be interpreted as meaning "at least one" or "one or more". Additionally, terms 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", and further, should be interpreted as including combinations of these elements with other than "A", "B", and "C".

Claims

1. A cavity device comprising: An inner housing includes a passage through which light generated by the excitation of laser gas within the interior space of the inner housing passes; An outer housing that surrounds at least a portion of the inner housing from the side of the direction of light travel; and Multiple partition walls, which are spaced apart and arranged side by side between the inner housing and the outer housing in the direction of light travel, are fixed to the inner housing and the outer housing.

2. The cavity device according to claim 1, wherein, The outer shell comprises: An outer main body portion that surrounds the inner housing from the side and includes an opening on the side; and A cover plate that covers the opening. The cover plate includes a protrusion that projects outwards from the side of the outer body portion.

3. The cavity device according to claim 2, wherein, The protrusion bends toward the side.

4. The cavity device according to claim 3, wherein, The length of the protrusion from the bend in the protrusion to the end of the protrusion is 100 mm or more and 150 mm or less.

5. The cavity device according to claim 1, wherein, The cavity device also has cooling fins disposed on the inner circumferential surface of the inner housing.

6. The cavity device according to claim 5, wherein, The cooling fins are multiple. The cooling fins are arranged side by side at intervals in the direction of light travel.

7. The cavity device according to claim 6, wherein, The partition walls and the cooling fins are arranged alternately along the direction of light travel.

8. The cavity device according to claim 7, wherein, The cooling fins are positioned between adjacent partition walls.

9. The cavity device according to claim 1, wherein, The gap between the inner and outer housings, divided by the partition wall, is a flow path for the cooling medium.

10. The cavity device according to claim 9, wherein, The cavity device further includes a passage located at the same position as the partition wall in the direction of light travel, through which the cooling medium flows from one of the adjacent gaps to the other.

11. The cavity device according to claim 10, wherein, The passage, positioned at the same location as one of the adjacent partition walls in the direction of light travel, and the passage, positioned at the same location as the other partition wall adjacent to the one partition wall in the direction of light travel, are positioned so as not to overlap when viewed along the direction of light travel.

12. The cavity device according to claim 9, wherein, The cavity device also includes a temperature regulator that adjusts the temperature of the cooling medium.

13. The cavity device according to claim 1, wherein, The outer housing includes a plate that surrounds the surface of the inner housing containing the passage opening. The plate is provided with a mirror that faces the passage and reflects at least a portion of the light.

14. The cavity device according to claim 1, wherein, The outer shell comprises: An outer main body portion that surrounds the inner housing from the side and includes an opening on the side; and A cover plate that covers the opening. The cover plate is provided with an insulating part and a sealing component, the sealing component sealing the space between the cover plate and the insulating part.

15. The cavity device according to claim 14, wherein, The cover plate is made of nickel alloy. The sealing component is a metal seal.

16. The cavity device according to claim 1, wherein, The thickness of the inner shell plate is less than 7mm.

17. The cavity device according to claim 1, wherein, The thickness of the outer shell plate is less than 3 mm.

18. The cavity device according to claim 1, wherein, The outer shell is thinner than the inner shell.

19. A method for manufacturing an electronic device, comprising the following steps: Laser is generated by a gas laser device with a cavity. The laser is output to the exposure device. The laser is exposed on a photosensitive substrate within the exposure apparatus to manufacture electronic devices. The cavity device has: An inner housing includes a passage through which light generated by the excitation of laser gas within the interior space of the inner housing passes; An outer housing that surrounds at least a portion of the inner housing from the side of the direction of light travel; and Multiple partition walls, which are spaced apart and arranged side by side between the inner housing and the outer housing in the direction of light travel, are fixed to the inner housing and the outer housing.

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