Chamber apparatus, gas laser apparatus, and method for manufacturing electronic device

Abstract

A chamber device according to one aspect of the present disclosure is provided with: a metal case in which an opening for accommodating a laser gas and a discharge electrode therein is formed, the end of the opening having a stepped shape over the entire circumference; a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing linear edges and four corners, and having a stepped end portion fitted over the entire circumference with the end portion of the opening so as to cover the opening; a pressing member that presses the two sets of opposing linear edges toward the open end in a state in which the four corners are open; a groove formed in a receiving surface so as to surround the opening, the receiving surface receiving an end portion of the electrically insulating plate at an end portion of the opening; and an O-ring disposed in the groove. In at least one of the four corners, a surface of the end portion of the electrically insulating plate facing the receiving surface includes a contact surface and a separation surface, the contact surface is in contact with the receiving surface and covers the groove, and the separation surface is separated from the receiving surface at a position closer to the outer peripheral side than the contact surface.

Description

Technical Field

[0001] This disclosure relates to methods for manufacturing chamber devices, gas laser 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, efforts are underway to shorten the wavelength of light emitted from the exposure light source. For example, as gas laser devices for exposure, KrF excimer lasers using lasers with an output wavelength of approximately 248 nm and ArF excimer lasers using lasers with an output wavelength of approximately 193 nm are being developed.

[0003] The spectral linewidth of the naturally oscillating light from KrF and ArF excimer lasers is as wide as 350 pm to 400 pm. Therefore, if the projection lens is made of a material that allows ultraviolet light, such as that from KrF and ArF lasers, to pass through, chromatic aberration can sometimes occur. 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 where chromatic aberration is negligible. Thus, in order to narrow the spectral linewidth, the laser resonator of a gas laser device sometimes includes a line-narrowing module (LNM) containing narrowing elements (etalon, grating, etc.). Hereinafter, gas laser devices with narrowed spectral linewidths will be referred to as narrow-band gas laser devices.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: US Patent No. 4,942,999

[0007] Patent Document 2: US Patent No. 5028162

[0008] Patent Document 3: Japanese Patent Application Publication No. 2001-102490 Summary of the Invention

[0009] One aspect of the cavity device disclosed herein comprises: a metallic housing having an opening for housing a laser gas and a discharge electrode therein, the end of the opening being stepped in shape around its circumference; a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing straight edges and four corners, and having a stepped end that fits around its circumference to cover the opening; a pressing member that presses the two sets of opposing straight edges toward the end of the opening with the four corners open; a groove formed on a receiving surface surrounding the opening, the receiving surface receiving the end of the electrically insulating plate at the end of the opening; and an O-ring disposed in the groove, at at least one of the four corners, the surface of the end of the electrically insulating plate facing the receiving surface including a contact surface and a separation surface, the contact surface contacting the receiving surface and covering the groove, the separation surface separating from the receiving surface at a position further outward than the contact surface.

[0010] One aspect of the gas laser device disclosed herein includes a chamber assembly, a pulsed power module, and a charger. The chamber assembly comprises: a metallic housing having an opening for housing the laser gas and discharge electrodes, the ends of which are stepped over the entire circumference; a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing linear edges and four corners, and having stepped ends that fit circumferentially with the ends of the opening to cover it; and a pressing member that, with the four corners open, presses the two sets of opposing linear edges... The edge is pressed towards the end of the opening; a groove is formed on the receiving surface in a manner that surrounds the opening, the receiving surface receiving the end of the electrical insulation plate at the end of the opening; and an O-ring is disposed in the groove, at least one of the four corners, the end of the electrical insulation plate facing the receiving surface includes a contact surface and a separation surface, the contact surface contacts the receiving surface and covers the groove, the separation surface separates from the receiving surface at a position further outward than the contact surface, the pulse power module is connected to the discharge electrode via a plurality of feedthroughs embedded in the electrical insulation plate, and the charger supplies voltage to the pulse power module.

[0011] One aspect of this disclosure relates to a method for manufacturing an electronic device, comprising the steps of: generating a laser using a gas laser device; outputting the laser to an exposure apparatus; and exposing the laser on a photosensitive substrate within the exposure apparatus to manufacture the electronic device. The gas laser device includes a chamber assembly, a pulsed power module, and a charger. The chamber assembly comprises: a metal housing having an opening for housing the laser gas and discharge electrodes therein, the ends of the opening being stepped over its entire circumference; and a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing straight edges and four corners, and having a stepped shape that fits around the circumference of the opening to cover its ends. The device comprises: an end portion of a shape; a pressing member that presses two sets of opposing straight edges toward the end of the opening with the four corners open; a groove formed on a receiving surface surrounding the opening, the receiving surface receiving the end of an electrical insulating plate at the end of the opening; and an O-ring disposed in the groove at at least one of the four corners, wherein the end of the electrical insulating plate facing the receiving surface includes a contact surface and a separation surface, the contact surface contacting the receiving surface and covering the groove, and the separation surface separating from the receiving surface at a position further outward than the contact surface; a pulse power module connected to a discharge electrode via multiple feedthroughs embedded in the electrical insulating plate; and a charger supplying a charging voltage to the pulse power module. Attached Figure Description

[0012] The following description, by way of example only, refers to the accompanying drawings to illustrate several embodiments of this disclosure.

[0013] Figure 1 This is a side view that schematically shows the structure of the comparative example gas laser device.

[0014] Figure 2 This is a top view showing the planar shape of the electrical insulation board.

[0015] Figure 3 This is a top view showing the structure of the electrical insulation plate and housing as viewed from above with the pulse power module removed.

[0016] Figure 4 This is a diagram showing the structure of the electrical insulation plate and the housing.

[0017] Figure 5 It shows along Figure 3 A sectional view of the section along line B1-B1.

[0018] Figure 6 This illustrates the situation where the housing and electrical insulation plate are heated by laser gas along the path. Figure 3 A sectional view of the section along line B1-B1.

[0019] Figure 7 This is a top view showing the structure of the corner of the electrical insulation plate as viewed from below.

[0020] Figure 8 This is a top view showing the structure of the electrical insulation plate and housing of the first embodiment as viewed from above with the pulse power module removed.

[0021] Figure 9 This is a diagram showing the structure of the electrical insulation plate and the housing according to the first embodiment.

[0022] Figure 10 It shows along Figure 8 A sectional view of the section along line B2-B2.

[0023] Figure 11 This illustrates the situation where the housing and electrical insulation plate are heated by laser gas along the path. Figure 8 A sectional view of the section along line B2-B2.

[0024] Figure 12 This is a top view showing the structure of the corner of the electrical insulation plate as viewed from below.

[0025] Figure 13 This is a graph showing the dependence of the maximum stress applied to the boundary on the length of line segment AE.

[0026] Figure 14 This is a top view showing a modified example of the planar shape of the separating surface.

[0027] Figure 15 This is a top view showing a modified example of the planar shape of the separating surface.

[0028] Figure 16 This is a top view showing a modified example of the planar shape of the separating surface.

[0029] Figure 17 This is a top view showing a modified example of the planar shape of the separating surface.

[0030] Figure 18 This is a cross-sectional view showing a modified example of the cross-sectional shape of the separation surface.

[0031] Figure 19 This is a cross-sectional view showing a modified example of the cross-sectional shape of the separation surface.

[0032] Figure 20 This is a cross-sectional view showing a modified example of the cross-sectional shape of the separation surface.

[0033] Figure 21 This is a top view showing the structure of the electrical insulation plate and housing of the second embodiment as viewed from above with the pulse power module removed.

[0034] Figure 22 This is a diagram showing the structure of the electrical insulation plate and housing according to the second embodiment.

[0035] Figure 23 It shows along Figure 21 A sectional view of the section along line B3-B3.

[0036] Figure 24 This illustrates the situation where the housing and electrical insulation plate are heated by laser gas along the path. Figure 21 A sectional view of the section along line B3-B3.

[0037] Figure 25 This is a top view showing the structure of the housing and the corner of the electrical insulation plate as viewed from below.

[0038] Figure 26 This is a top view showing a modified example of the planar shape of the cut.

[0039] Figure 27 This is a top view showing a modified example of the planar shape of the cut.

[0040] Figure 28 This is a top view showing a modified example of the planar shape of the cut.

[0041] Figure 29 This is a diagram that roughly illustrates an example of the structure of an exposure apparatus. Detailed Implementation

[0042] <Content>

[0043] 1. Comparative Example

[0044] 1.1 Gas Laser Device

[0045] 1.1.1 Structure

[0046] 1.1.2 Actions

[0047] 1.2 Electrical insulation board

[0048] 1.3 Research Topic

[0049] 2. First Implementation Method

[0050] 2.1 Structure

[0051] 2.2 Functions and Effects

[0052] 2.3 Variations of the First Embodiment

[0053] 3. Second Implementation Method

[0054] 3.1 Structure

[0055] 3.2 Functions and Effects

[0056] 3.3 Variations of the Second Embodiment

[0057] 4. Manufacturing methods for electronic devices

[0058] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The embodiments described below illustrate several examples of the present disclosure and do not limit the content of the present disclosure. In addition, the structures and operations described in the embodiments are not necessarily all necessary for the structures and operations of the present disclosure. Furthermore, the same reference numerals are used to refer to the same constituent elements, and repeated descriptions are omitted.

[0059] 1. Comparative Example

[0060] First, the comparative examples of this disclosure will be explained. The comparative examples of this disclosure are those known only to the applicant and are not publicly known examples that the applicant himself acknowledges.

[0061] 1.1 Gas Laser Device

[0062] 1.1.1 Structure

[0063] use Figure 1 The structure of the gas laser device 2 in the comparative example is explained. Figure 1 The structure of the gas laser device 2 is shown in outline. The gas laser device 2 is a discharge-excited gas laser device, such as an excimer laser device, which excites the laser gas by discharge.

[0064] exist Figure 1 In this context, the travel direction of the pulsed laser PL output from the gas laser device 2 is defined as the Z direction. The discharge direction, described later, is defined as the Y direction. Furthermore, the direction orthogonal to both the Z and Y directions is defined as the X direction.

[0065] exist Figure 1 In this configuration, the gas laser device 2 includes a cavity device 3, a charger 4, a pulsed power module (PPM) 5, a monitoring module 6, a processor 7, and an optical resonator. The optical resonator consists of a narrowband module 8 and an output coupling mirror 9.

[0066] The chamber device 3 is configured to include a housing 10 and an electrically insulating plate 11. An opening 10a for receiving laser gas and a discharge electrode 12 is formed at the upper end of the housing 10. For example, the chamber device 3 is a container made of a metal such as aluminum with a nickel plating on its surface. The electrically insulating plate 11 is fixed to the housing 10 by blocking the opening 10a of the housing 10. The electrically insulating plate 11 is formed of a ceramic such as alumina (Al2O3).

[0067] Inside the housing 10 are a discharge electrode 12, a ground plane 13, and a fan 14. Additionally, a fluorine-containing laser gas is sealed inside the housing 10 as the laser medium. The laser gas may include, for example, rare gases such as argon, krypton, and xenon; buffer gases such as neon and helium; or halogen gases such as fluorine and chlorine.

[0068] The electrical insulation plate 11 is fixed to the housing 10 by covering the opening 10a of the housing 10. Multiple feedthrough sections 15 are embedded in the electrical insulation plate 11. PPM5 is disposed on the electrical insulation plate 11. The housing 10 is grounded.

[0069] The PPM5 is connected to the discharge electrode 12 via multiple feedthroughs 15. The PPM5 includes a switch SW for discharging the discharge electrode 12. The charger 4 is connected to a charging capacitor (not shown) included with the PPM5 to supply voltage to the PPM5.

[0070] The discharge electrode 12 consists of a cathode electrode 12a and an anode electrode 12b. The cathode electrode 12a and the anode electrode 12b are arranged within the housing 10 with their discharge surfaces facing each other. Hereinafter, the space between the cathode electrode 12a and the anode electrode 12b will be referred to as the discharge space. The discharge direction is the direction in which the cathode electrode 12a and the anode electrode 12b face each other.

[0071] The side of the cathode electrode 12a opposite to the discharge surface is supported by an electrically insulating plate 11 and connected to a plurality of feedthrough sections 15. The side of the anode electrode 12b opposite to the discharge surface is supported by a ground plane 13.

[0072] Fan 14 is a crossflow fan used to circulate laser gas within housing 10, and is positioned in the space opposite to the discharge space from ground plane 13. A motor 14a is connected to housing 10 to drive the rotation of fan 14. Additionally, a heat exchanger (not shown) is disposed inside housing 10.

[0073] Windows 16a and 16b are provided on the side wall of the housing 10 for emitting light generated inside the housing 10 to the outside. The housing 10 is configured such that the optical path of the optical resonator passes through the discharge space and the windows 16a and 16b.

[0074] The narrowband module 8 includes a prism 8a, a grating 8b, and a rotating stage 8c. The prism 8a allows light emitted from the chamber device 3 through the window 16a to pass through with a wider beam and toward the grating 8b side.

[0075] The grating 8b is configured in a Littrow configuration where the incident angle and diffraction angle are the same. The prism 8a is supported by a rotating stage 8c, which rotates the prism 8a, changing the incident angle of light towards the grating 8b. The grating 8b is a wavelength-selective element that selectively extracts light near a specific wavelength based on the diffraction angle. The spectral linewidth of the light returning from the grating 8b to the chamber device 3 via the prism 8a is narrowed.

[0076] The output coupling mirror 9 allows a portion of the light emitted from the chamber device 3 via window 16b to pass through, while reflecting the remaining portion back into the chamber device 3. A partially reflective coating is applied to the surface of the output coupling mirror 9.

[0077] The light emitted from the chamber device 3 oscillates between the narrowband module 8 and the output coupling mirror 9, and is amplified each time it passes through the discharge space. A portion of the amplified light is output as a pulsed laser PL via the output coupling mirror 9. Furthermore, the pulsed laser PL is an example of the "laser" in the present disclosure.

[0078] The monitoring module 6 is configured in the optical path of the pulsed laser PL output via the output coupling mirror 9. The monitoring module 6 includes a beam splitter 6a, a focusing optical system 6b, and a light sensor 6c.

[0079] Beam splitter 6a allows the pulsed laser PL to pass through with high transmittance and reflects a portion of the pulsed laser PL toward the focusing optical system 6b. The focusing optical system 6b focuses the light reflected by the beam splitter 6a onto the light-receiving surface of the optical sensor 6c. The optical sensor 6c measures the pulse energy E and wavelength λ of the light focused onto the light-receiving surface and outputs the measured values ​​to the processor 7.

[0080] The processor 7 is a processing device that transmits and receives various signals between itself and the exposure device controller 110 provided in the exposure device 100. For example, the exposure device controller 110 sends the target pulse energy Et, target wavelength λt, oscillation trigger signal, etc. of the pulsed laser PL to be output to the exposure device 100 to the processor 7.

[0081] The processor 7 controls the operation of each component of the gas laser device 2 in a unified manner based on various signals sent from the exposure device controller 110, the measured values ​​of pulse energy E and wavelength λ.

[0082] 1.1.2 Actions

[0083] Next, the operation of the comparative example gas laser device 2 will be described. The processor 7 receives the target pulse energy Et, the target wavelength λt, and the oscillation trigger signal from the exposure device controller 110 of the exposure device 100.

[0084] The processor 7 sets a charging voltage for the charger 4 corresponding to the target pulse energy Et. Furthermore, the processor 7 synchronizes the operation of the switch SW within the PPM5 with the oscillation trigger signal, thereby applying a high voltage between the cathode electrode 12a and the anode electrode 12b. As a result, a discharge is generated in the discharge space, exciting the laser gas and causing laser oscillation in the optical resonator. At this time, a pulsed laser PL, narrowed by the narrowing module 8, is output from the output coupling mirror 9.

[0085] The pulsed laser PL output from the output coupling mirror 9 is incident on the monitoring module 6, and the pulse energy E and wavelength λ are measured by the monitoring module 6. The pulsed laser PL, passing through the beam splitter 6a of the monitoring module 6, is incident on the exposure apparatus 100.

[0086] Processor 7 controls the charging voltage to make the difference between the target pulse energy Et and the measured pulse energy E close to 0. Additionally, processor 7 controls the rotating stage 8c to make the difference between the target wavelength λt and the measured wavelength λ close to 0.

[0087] In addition, Figure 1 In this example, an excimer laser device is shown as a gas laser device 2, but the gas laser device 2 can also be an F2 laser device or the like that uses a laser gas containing fluorine gas and a buffer gas.

[0088] 1.2 Electrical insulation board

[0089] Next, the structure of the electrical insulation board 11 will be described. Figure 2 The planar shape of the electrical insulation plate 11 is shown. Figure 3 The structure of the electrical insulation plate 11 and the housing 10 is shown from above with the PPM5 removed.

[0090] The upper surface 11a of the electrical insulating plate 11 is generally rectangular, having a planar shape surrounded by a pair of first edges H1 opposed in the X direction, a pair of second edges H2 opposed in the Y direction, and four corners 11b. The first edges H1 and the second edges H2 are both straight. The corners 11b connect the first edges H1 and the second edges H2. The pair of first edges H1 and the pair of second edges H2 correspond to the "two sets of opposed straight edges" of the present disclosure.

[0091] like Figure 2 As shown, the corner 11b includes a chamfered portion BV formed by cutting off the end of the electrical insulating plate 11 in a direction inclined relative to the first edge H1 and the second edge H2. K represents the cut-off portion.

[0092] like Figure 3As shown, the electrical insulation plate 11 is fixed to the housing 10 by pressing it against four pressing plates 20 and a plurality of bolts 21. For example, the pressing plates 20 are made of stainless steel. The four pressing plates 20 are an example of the "pressing components" of the present disclosure.

[0093] Specifically, the four pressing plates 20 are arranged to cover two sets of opposing straight edges H1, H2 around the electrical insulation plate 11. However, it is preferable that the four pressing plates 20 completely cover the periphery of the electrical insulation plate 11, but the four corners 11b are left open due to the need to arrange other components near the corners 11b of the electrical insulation plate 11. That is, the four pressing plates 20 press the two sets of opposing straight edges H1, H2 against the ends of the opening 10a with the four corners 11b open.

[0094] Multiple feedthrough sections 15 are arranged at equal intervals along the length direction, i.e., the Z direction, of the electrical insulation plate 11.

[0095] Figure 4 The structure of the electrical insulation plate 11 and the housing 10 is shown. Figure 4 (A) shows along Figure 3 The cross section of line A1-A1. Figure 4 (B) shows the structure of the electrical insulation plate 11 as viewed from below.

[0096] like Figure 4 As shown in (A), the electrical insulating plate 11 is composed of a base 30 and an electrode fixing portion 31 with a planar shape smaller than that of the base 30. The base 30 and the electrode fixing portion 31 are integrally formed from the aforementioned ceramic. The electrode fixing portion 31 is positioned closer to the inside of the housing 10 than the base 30. That is, the upper surface 11a of the electrical insulating plate 11 is the upper surface of the base 30. A cathode electrode 12a is fixed on the lower surface 11c of the electrical insulating plate 11, i.e., the surface of the electrode fixing portion 31.

[0097] Since the planar shape of the electrode fixing portion 31 is smaller than that of the base portion 30, the outer edge portion 30a of the base portion 30 extends outward compared to the electrode fixing portion 31 over the entire circumference. Therefore, the end of the electrical insulating plate 11 is formed in a stepped shape that includes the boundary portion 32 between the base portion 30 and the electrode fixing portion 31.

[0098] A receiving portion 40 for receiving an electrical insulating plate 11 is formed in the housing 10. The receiving portion 40 extends inward from the inner wall of the housing 10 along its entire circumference. The end of the receiving portion 40 forms the opening 10a described above. Therefore, the housing 10 is formed in a stepped shape to fit into the end of the stepped electrical insulating plate 11 in a manner that blocks the opening 10a. The outer edge 30a of the base 30 contacts the upper surface of the receiving portion 40. The outer edge 30a is fixed between the receiving portion 40 and the pressing plate 20. The electrode fixing portion 31 is disposed at a position further inward than the end of the opening 10a.

[0099] An annular groove 41 is formed on the upper surface of the receiving portion 40, surrounding the opening 10a in the XZ plane. To maintain the airtightness of the housing 10, an O-ring 42 with a cross-sectional diameter larger than the depth of the groove 41 is disposed in the groove 41. The O-ring 42 is made of metal, elastomer, resin, etc. The O-ring 42 is pressed from the outer edge 30a of the base 30, thereby sealing the upper surface of the receiving portion 40 and the outer edge 30a.

[0100] like Figure 4 As shown in (B), in the XZ plane, the O-ring 42 surrounds the boundary portion 32, and the boundary portion 32 surrounds the electrode fixing portion 31.

[0101] Figure 5 Show along Figure 3 The cross-section of line B1-B1. Figure 5 For ease of explanation, the electrical insulation plate 11 is positioned away from the housing 10 in the Y direction. The upper surface of the receiving portion 40 is the surface that receives the outer edge portion 30a of the base portion 30, and is therefore referred to as the receiving surface 43 below. The receiving surface 43 is planar except for the groove 41. Furthermore, the lower surface of the outer edge portion 30a is the surface that contacts the receiving surface 43, and is therefore referred to as the contact surface 33 below. The contact surface 33 is planar and is in contact with the receiving surface 43 entirely.

[0102] 1.3 Research Topic

[0103] When the gas laser device 2 is activated, the laser gas sealed inside the housing 10 becomes high-temperature, thus heating the housing 10 and the electrical insulation plate 11. The housing 10 is made of a metal such as aluminum, while the electrical insulation plate 11 is made of a ceramic such as alumina. Therefore, the thermal expansion coefficients of the housing 10 and the electrical insulation plate 11 are different.

[0104] Figure 6 The image shows the case where the housing 10 and the electrical insulation plate 11 are heated by laser gas. Figure 3The cross-section of line B1-B1. The coefficient of thermal expansion of the housing 10 is greater than that of the electrical insulation plate 11. Therefore, when the housing 10 and the electrical insulation plate 11 are heated, the contact surface 33 of the electrical insulation plate 11 is subjected to stress in the Y direction from the receiving surface 43 of the housing 10. Since no pressing plate 20 is provided at the corner 11b of the electrical insulation plate 11, a bending moment is generated with the boundary portion 32 as the fulcrum due to the stress on the contact surface 33. This bending moment can occur at any corner of the four corners 11b.

[0105] Figure 7 The structure of the corner 11b of the electrical insulation plate 11, viewed from below, is shown. Figure 7 In the middle, the housing 10 is not shown. (As shown) Figure 7 As shown, at corner 11b, the boundary 32 is an arc centered at point O.

[0106] exist Figure 7 In the diagram, A to D are imaginary points located at the ends of the outer edge 30a of the electrical insulation plate 11. E is the intersection point where the imaginary line extending segment AB intersects the imaginary line extending segment DC. Triangle BCE corresponds to the cut-off portion K. Segment BC corresponds to the chamfered portion BV. Imaginary points B and C are selected such that segment BC does not contact the outermost end of the groove 41. In this comparative example, segment BC is set at an angle of 45° to intersect the X and Z directions.

[0107] Imaginary point A is located at the Z-direction end of the outer edge 30a. F1 is the intersection point of the line connecting the center point O and imaginary point B with the boundary 32. F2 is the intersection point of the line connecting the center point O and imaginary point A with the boundary 32. Let L be the distance between intersection point F1 and imaginary point B. F1B Let L be the distance between the intersection point F2 and the imaginary point A. F2A In the case of L F1B >L F2A The relationship always holds true.

[0108] The magnitude of the bending moment generated at the boundary portion 32 is proportional to the distance from the boundary portion 32 to the end of the contact surface 33. Since the distance from imaginary point B to the boundary portion 32 is greater than the distance from imaginary point A to the boundary portion 32, the bending moment acting at imaginary point B is always greater than the bending moment acting at imaginary point A. The relationship between imaginary points D and C located at the X-direction end of the outer edge portion 30a can also be described as the same.

[0109] Thus, the bending moment generated at the boundary 32 increases at the corner 11b of the electrical insulation plate 11. When the bending moment increases, cracks may occur at the boundary 32. Therefore, it is desirable to reduce the bending moment generated at the boundary 32.

[0110] 2. First Implementation Method

[0111] 2.1 Structure

[0112] The gas laser device 2 of the first embodiment of this disclosure has the same structure as the gas laser device 2 of the comparative example, except that the structure of the electrical insulation plate 11 is different.

[0113] Figure 8 The structure of the electrical insulation plate 11 and housing 10 of the first embodiment is shown from above when the PPM5 is removed. Figure 9 The structure of the electrical insulation plate 11 and the housing 10 of the first embodiment is shown. Figure 9 (A) shows along Figure 8 The cross section of line A2-A2. Figure 9 (B) shows the structure of the electrical insulation plate 11 of the first embodiment as viewed from below. The only difference between the electrical insulation plate 11 of the first embodiment and the comparative example is that cutouts 50 are formed on the lower surface side of each of the four corner portions 11b.

[0114] Figure 10 Show along Figure 8 The cross-section of line B2-B2. Figure 10 For ease of explanation, the electrical insulation plate 11 is positioned away from the housing 10 in the Y direction. In the electrical insulation plate 11, a cutout 50 is formed at the corner 11b by cutting off the end of the outer edge 30a facing the receiving surface 43. By forming the cutout 50 in the electrical insulation plate 11, a separation surface 34 is formed, separating it from the receiving surface 43 in the Y direction.

[0115] The separating surface 34 is separated from the receiving surface 43 at a position further outward than the contact surface 33. That is, the separating surface 34 is a non-contact surface that does not contact the receiving surface 43. In this embodiment, both the separating surface 34 and the receiving surface 43 are planar, and the distance between the separating surface 34 and the receiving surface 43 is fixed. The contact surface 33 contacts the receiving surface 43 in a manner that covers the groove 41.

[0116] Figure 11 The image shows the case where the housing 10 and the electrical insulation plate 11 are heated by laser gas. Figure 8 The cross section of line B2-B2. In this embodiment, the separating surface 34 is not subjected to stress from the receiving surface 43, so the magnitude of the bending moment with the boundary portion 32 as the fulcrum is smaller than that in the comparative example. The depth of the cut portion 50 in the Y direction is preferably a value greater than or equal to the thermal deformation of the housing 10, for example, preferably 0.1 mm or more, so that the separating surface 34 does not contact the receiving surface 43.

[0117] Figure 12The structure of the corner 11b of the electrical insulation plate 11, viewed from below, is shown. A separation surface 34 is formed between the area corresponding to the groove 41 and the chamfered portion BV. The separation surface 34 has a shape with the chamfered portion BV as one side and four vertices. For example, the separation surface 34 is a quadrilateral.

[0118] exist Figure 12 In the diagram, A to D are imaginary points located at the ends of the outer edge 30a of the electrical insulation plate 11. Similar to the comparative example, triangle BCE corresponds to the cut-off portion K described above. Imaginary point A is located at the Z-direction end of the outer edge 30a, and is located further away from imaginary point E than imaginary point B. Imaginary point D is located at the X-direction end of the outer edge 30a, and is located further away from imaginary point E than imaginary point C.

[0119] In this embodiment, the region enclosed by imaginary points A to D is the separation surface 34. Imaginary points A and D are positioned such that line segment AD does not contact the outermost end of groove 41. In this embodiment, line segment BC is parallel to line segment AD. Therefore, the separation surface 34 is trapezoidal. Furthermore, the angle θ1 formed by line segment BC and line segment CE and the angle θ2 formed by line segment AD and line segment DE are equal, both being 45°.

[0120] In this embodiment, line segment AD is parallel to line segment BC, but they may not be parallel. That is, the separating surface 34 is not limited to a trapezoid, but may also be a quadrilateral other than a trapezoid. For example, the separating surface 34 may also be a region surrounded by imaginary points A', B, C, and D. In this case, the imaginary points A' and D are selected in such a way that line segment A'D does not contact the outermost end of the groove 41. Alternatively, the separating surface 34 may also be a region surrounded by imaginary points A, B, C, and D'. In this case, the imaginary points A and D' are selected in such a way that line segment AD' does not contact the outermost end of the groove 41.

[0121] 2.2 Functions and Effects

[0122] In this embodiment, a separation surface 34 is formed on the electrical insulation plate 11. Therefore, the longest distance from the boundary portion 32 to the Z-direction end of the contact surface 33 is the distance L from the intersection point F1 to the imaginary point B. F1B Change to the distance L from intersection point F2 to imaginary point A F2A The relationship between hypothetical point D and hypothetical point C can also be described as the same. Thus, in this embodiment, by providing the separation surface 34, the distance from the boundary portion 32 to the end of the contact surface 33 is reduced, thereby decreasing the bending moment generated at the boundary portion 32. As a result, crack formation is suppressed, and the lifespan of the electrical insulation plate 11 is extended.

[0123] Furthermore, when the separation surface 34 is a region surrounded by imaginary points A', B, C, and D, the longest distance from the boundary portion 32 to the Z-direction end of the contact surface 33 becomes the distance L from the intersection point F3 to the imaginary point A'. F3A’ The distance from the boundary portion 32 to the end of the contact surface 33 is further reduced. The same applies to the separation surface 34, which is the region surrounded by imaginary points A, B, C, and D'.

[0124] Figure 13 This shows the dependence of the maximum stress applied to boundary portion 32 on the length of line segment AE. The stress applied to boundary portion 32 is the bending stress corresponding to the bending moment. Figure 13 These are simulation results under the condition that θ1 = θ2 = 45° and the depth of the cut 50 in the Y direction is 0.6 mm. The length of line segment AE is equal to the length of line segment DE. The horizontal axis represents the maximum length of line segment AE when line segment AD does not contact the outermost end of groove 41 as 100%. The vertical axis represents the maximum stress applied to boundary portion 32 in the comparative example as 100%.

[0125] In the comparative example, where line segment AE overlaps with line segment BC, the length of line segment AE is 48% of its maximum length. The maximum stress applied to the boundary portion 32 decreases as the length of line segment AE increases. When the length of line segment AE is 100%, i.e., when the area of ​​the separation surface 34 is at its maximum, the maximum stress applied to the boundary portion 32 is suppressed to approximately 50%.

[0126] 2.3 Variations of the First Embodiment

[0127] The following describes various variations of the first embodiment.

[0128] In the above embodiment, the shape of the separating surface 34 is set to a quadrilateral, but it can be any shape other than a quadrilateral, as long as it is surrounded by a line passing through four imaginary points at the end of the outer edge 30a. For example, Figure 14 As shown, line segment AD does not have to be a completely straight line; the two ends of a straight line segment AD can be curved.

[0129] In addition, such as Figure 15 As shown, line segment AD can also be a curve that is concave towards the center point O. More specifically, line segment AD can also be an arc centered at the center point O. In this case, the distance L from the boundary portion 32 to line segment AD at the corner 11b is equal at any position, so the stress applied to the boundary portion 32 at the corner 11b becomes uniform. This suppresses stress concentration, thus further suppressing damage to the boundary portion 32.

[0130] In addition, such as Figure 16As shown, line segment AD can also be a curve that bulges outwards from the center point O. In this case, line segment AD can also be an arc with the same curvature as the boundary portion 32.

[0131] Furthermore, in the above embodiment, a chamfered portion BV is formed at the corner 11b, but it is not necessary to form a chamfered portion BV. That is, the electrical insulating plate 11 can also be a rectangle without the chamfered portion BV. In this case, such as Figure 17 As shown, the separating surface 34 is a shape with three vertices. Specifically, the separating surface 34 is a triangle with imaginary points A, D, and E as vertices. The shape of the separating surface 34 can also be a right triangle or an isosceles right triangle. Furthermore, in this case, the separating surface 34 can be any shape enclosed by a line passing through the three imaginary points, and it doesn't have to be a triangle. Line segment AD can be... Figures 14-16 The same transformation.

[0132] Furthermore, in the above embodiment, the spacing between the separating surface 34 and the receiving surface 43 formed in the cut portion 50 is fixed, but as... Figures 18-20 As shown, the cutout 50 can also be formed such that the distance between the separating surface 34 and the receiving surface 43 increases towards the outer edge 30a. In this case, the angle at the end of the contact surface 33 becomes larger, thus suppressing damage to the end of the contact surface 33.

[0133] Figure 18 An example is shown where the rate of increase of the distance between the separating surface 34 and the receiving surface 43 is constant. In this case, the separating surface 34 is planar. Figure 19 An example is shown where the rate of increase of the distance between the separating surface 34 and the receiving surface 43 decreases toward the outer periphery. In this case, the separating surface 34 is concave. Figure 20 An example is shown where the rate of increase of the distance between the separating surface 34 and the receiving surface 43 increases toward the outer periphery. In this case, the separating surface 34 is convex.

[0134] Furthermore, in the above embodiment, cutouts 50 are formed at all four corners 11b, but it is sufficient for cutouts 50 to be formed at at least one of the four corners 11b. For example, cutouts 50 may be formed at two of the four corners 11b, or cutouts 50 may be formed at three of the four corners 11b.

[0135] 3. Second Implementation Method

[0136] 3.1 Structure

[0137] The gas laser device 2 of the second embodiment of this disclosure has the same structure as the gas laser device 2 of the first embodiment, except that the structures of the electrical insulation plate 11 and the housing 10 are different.

[0138] Figure 21 The structure of the electrical insulation plate 11 and housing 10 of the second embodiment is shown from above with the PPM5 removed. Figure 22 The structure of the electrical insulation plate 11 and the housing 10 of the second embodiment is shown. Figure 22 (A) shows along Figure 21 The cross section of line A3-A3. Figure 22 (B) shows the structure of the electrical insulation plate 11 of the second embodiment as viewed from below.

[0139] The electrical insulation plate 11 in the second embodiment has the same structure as the electrical insulation plate 11 in the comparative example, but without the cutout portion 50. In this embodiment, cutout portions 60 are formed by partially cutting off the areas corresponding to the four corner portions 11b of the housing 10.

[0140] Figure 23 Show along Figure 21 The cross-section of line B3-B3. Figure 23 For ease of explanation, the electrical insulation plate 11 is positioned away from the housing 10 in the Y direction. In the housing 10, at the corner 11b, a cutout 60 is formed by cutting away a portion of the surface opposite the end of the outer edge 30a of the electrical insulation plate 11. By forming the cutout 60 in the housing 10, the end of the outer edge 30a is separated from the receiving surface 43 in the Y direction. The portion of the lower surface of the outer edge 30a opposite the cutout 60 functions as a separation surface 34. In this embodiment, in addition to the surface where the groove 41 is formed, the bottom surface of the cutout 60 is also referred to as the receiving surface 43.

[0141] Similar to the first embodiment, the separating surface 34 is separated from the receiving surface 43 at a position further outward than the contact surface 33, and is opposite to the receiving surface 43. That is, the separating surface 34 is a non-contact surface that does not contact the receiving surface 43. In this embodiment, the distance between the separating surface 34 and the receiving surface 43 is fixed. The contact surface 33 contacts the receiving surface 43 in a manner that covers the groove 41.

[0142] Figure 24 The image shows the case where the housing 10 and the electrical insulation plate 11 are heated by laser gas. Figure 21 The cross section of line B3-B3. In this embodiment, the separating surface 34 is not subjected to stress from the receiving surface 43, so the bending moment with the boundary portion 32 as the fulcrum is smaller than that in the comparative example. The depth of the cut portion 60 in the Y direction is preferably a value greater than or equal to the thermal deformation of the housing 10, for example, preferably 0.1 mm or more, so that the separating surface 34 does not contact the receiving surface 43.

[0143] Figure 25The structure of the corner 11b of the housing 10 and the electrical insulation plate 11, viewed from below, is shown. A separation surface 34 is formed between the area corresponding to the groove 41 and the chamfered portion BV. The separation surface 34 has a shape with four vertices. For example, the separation surface 34 is a quadrilateral.

[0144] exist Figure 25 In this embodiment, A to D are imaginary points located at the ends of the outer edge 30a of the electrical insulation plate 11. In this embodiment, the area enclosed by imaginary points A to D is also called the separation surface 34. In this embodiment, line segment AD is parallel to line segment BC, but they may not be parallel. The shape of the separation surface 34 can be modified in the same way as in the first embodiment. That is, the separation surface 34 is not limited to a trapezoid, but may also be a quadrilateral other than a trapezoid.

[0145] The points where the extension of line segment AD intersects the end of the receiving part 40 are defined as A' and D', respectively; the point where the extension of line segment OB intersects the end of the receiving part 40 is defined as B'; and the point where the extension of line segment OC intersects the end of the receiving part 40 is defined as C'. The cut portion 60 is the area surrounded by A', B', C', and D'.

[0146] 3.2 Functions and Effects

[0147] In this embodiment, similar to the first embodiment, a separation surface 34 is formed on the electrical insulation plate 11. Therefore, the longest distance L from the boundary portion 32 to the Z-direction end of the contact surface 33 is the distance L from the intersection point F1 to the imaginary point B. F1B Change to the distance L from intersection point F2 to imaginary point A F2A The relationship between hypothetical point D and hypothetical point C can also be described as the same. Thus, in this embodiment, by providing the separation surface 34, the distance from the boundary portion 32 to the end of the contact surface 33 is reduced, thereby decreasing the bending moment generated at the boundary portion 32. As a result, crack formation is suppressed, and the lifespan of the electrical insulation plate 11 is extended.

[0148] 3.3 Variations of the Second Embodiment

[0149] The following describes various variations of the second embodiment.

[0150] In the above embodiment, a portion of the planar shape of the cut portion 60, namely line segment AA' and line segment DD', is respectively set as a straight line, but it can also be as follows: Figure 26 As shown, line segments AA' and DD' are respectively set as curves.

[0151] Furthermore, in the above embodiment, a portion of the planar shape of the cut portion 60, namely the line segment AD, is set to a straight line, but as... Figure 27As shown, line segment AD can also be a curve that bulges outwards from the center point O. In this case, line segment AD can also be an arc with the same curvature as the boundary portion 32. Furthermore, with... Figure 26 Similarly, line segments AA' and DD' can also be curved.

[0152] In addition, such as Figure 28 As shown, line segment AD can also be a curve that is concave towards the center point O. More specifically, line segment AD can also be an arc centered at the center point O. In this case, the distance L from the boundary portion 32 to line segment AD at the corner 11b is equal at any position, so the stress applied to the boundary portion 32 at the corner 11b becomes uniform. This suppresses stress concentration, thus further suppressing damage to the boundary portion 32. Furthermore, with... Figure 26 Similarly, line segments AA' and DD' can also be curved.

[0153] In addition, in the above embodiment, cutouts 60 are formed in all regions corresponding to the four corners 11b, but it is sufficient to form cutouts 60 in only the region corresponding to at least one corner 11b.

[0154] 4. Manufacturing methods for electronic devices

[0155] Figure 29 An example of the structure of the exposure apparatus 100 is schematically shown. The exposure apparatus 100 includes an illumination optics system 104 and a projection optics system 106. The illumination optics system 104 illuminates, for example, a mask pattern (not shown) disposed on a mask stage RT using a pulsed laser PL generated by and incident from a gas laser device 2. The projection optics system 106 reduces and projects the pulsed laser PL passing through the mask onto a workpiece (not shown) disposed on a workpiece stage WT. The workpiece is a photosensitive substrate such as a semiconductor wafer coated with photoresist.

[0156] The exposure apparatus 100 exposes a pulsed laser PL reflecting the mask pattern onto a workpiece by synchronously and parallelly moving the mask stage RT and the workpiece stage WT. After transferring the mask pattern onto a semiconductor wafer through the above exposure process, a semiconductor device can be manufactured through multiple processes. The semiconductor device is an example of the "electronic device" in this disclosure.

[0157] Furthermore, the gas laser device 2 is not limited to the manufacture of electronic devices, but can also be used for laser processing such as hole drilling.

[0158] The foregoing description is not intended to be limiting but merely illustrative. Therefore, it will be apparent to those skilled in the art that modifications can be made to the various embodiments of this disclosure without departing from the appended claims.

[0159] The terms used in this specification and the appended claims shall be interpreted as “non-limiting” terms. For example, the terms “comprising” or “including” shall be interpreted as “not limited to the portion described as included.” The term “having” shall be interpreted as “not limited to the portion described as having.” Furthermore, the phrase “an” in this specification and the appended claims shall be interpreted as “at least one” or “one or more.” In addition, terms such as “at least one of A, B, and C” shall be interpreted as “A,” “B,” “C,” “A+B,” “A+C,” “B+C,” or “A+B+C,” and shall also be interpreted as including combinations thereof with content other than “A,” “B,” and “C.”

Claims

1. A chamber device comprising: a metal housing formed with an opening for housing a laser gas and a discharge electrode inside, the opening having a stepped shape at an end portion thereof on the entire circumference; a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing linear edges and four corners, and having an end portion of a stepped shape fitted to the end portion of the opening on the entire circumference in a manner of covering the opening; a pressing member pressing the two sets of opposing linear edges to the end portion of the opening in a state where the four corners are open; a groove formed in a receiving surface in a manner of surrounding the opening, the receiving surface receiving the end portion of the electrically insulating plate at the end portion of the opening; and an O-ring disposed in the groove, wherein in at least one of the four corners, a surface of the end portion of the electrically insulating plate opposite to the receiving surface includes a contact surface and a separation surface, the contact surface being in contact with the receiving surface to cover the groove, the separation surface being separated from the receiving surface at a position on an outer circumferential side than the contact surface.

2. The chamber device according to claim 1, wherein in all of the four corners, the surface of the end portion of the electrically insulating plate opposite to the receiving surface includes the contact surface and the separation surface.

3. The chamber device according to claim 1, wherein the contact surface and the separation surface are respectively planar, and a distance between the contact surface and the separation surface is fixed.

4. The chamber device according to claim 1, wherein in at least one of the four corners, a chamfer portion is formed by cutting the end portion of the electrically insulating plate.

5. The chamber device according to claim 4, wherein the separation surface is a shape having four vertices with the chamfer portion as one side.

6. The chamber device according to claim 5, wherein the separation surface is a quadrilateral.

7. The chamber device according to claim 6, wherein the separation surface is a trapezoid.

8. The chamber device according to claim 1, wherein the electrically insulating plate is a long rectangle without the chamfer portion.

9. The chamber device according to claim 8, wherein the separation surface is a shape having three vertices.

10. The chamber device according to claim 9, wherein the separation surface is a right triangle or an isosceles right triangle.

11. The chamber device according to claim 1, wherein a distance between the contact surface and the separation surface is larger toward an outer circumferential side.

12. The chamber device according to claim 1, wherein the separation surface is formed by partially cutting a region of the housing corresponding to at least one of the four corners.

13. The chamber device according to claim 1, wherein the electrically insulating plate is composed of a base portion and an electrode fixing portion having a planar shape smaller than the base portion, and the electrode fixing portion is disposed at a position on an inner side of the housing than the base portion.

14. The chamber device according to claim 13, wherein the contact surface and the separation surface are formed at an outer edge portion of the base portion which protrudes outwardly than the electrode fixing portion.

15. The chamber device according to claim 14, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The housing is formed with a receiving portion extending inward from an inner wall, and the receiving surface is formed in the receiving portion.

16. A gas laser device, wherein The gas laser device includes a chamber device, a pulse power module, and a charger, The chamber device includes: a metal housing formed with an opening for receiving laser gas and a discharge electrode into an interior, an end portion of the opening being a stepped shape on an entire circumference; a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing linear edges and four corners, and having a stepped end portion fitting the end portion of the opening on the entire circumference in a manner of covering the opening; a pressing member pressing the two sets of opposing linear edges toward the end portion of the opening in a state of leaving the four corners open; a groove formed in a receiving surface in a manner of surrounding the opening, the receiving surface receiving the end portion of the electrically insulating plate at the end portion of the opening; and an O-ring disposed in the groove, in at least one of the four corners, a surface of the end portion of the electrically insulating plate opposite to the receiving surface includes a contact surface and a separation surface, the contact surface contacting the receiving surface to cover the groove, the separation surface separating from the receiving surface at a position on an outer circumferential side than the contact surface, the pulse power module is connected to the discharge electrode via a plurality of feedthroughs embedded in the electrically insulating plate, the charger supplies a voltage to the pulse power module.

17. A method of manufacturing an electronic device, wherein The method for manufacturing an electronic device includes the steps of: generating laser light by a gas laser device; 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, The gas laser device includes a chamber device, a pulse power module, and a charger, The chamber device includes: a metal housing formed with an opening for receiving laser gas and a discharge electrode into an interior, an end portion of the opening being a stepped shape on an entire circumference; a ceramic electrically insulating plate having a planar shape surrounded by two sets of opposing linear edges and four corners, and having a stepped end portion fitting the end portion of the opening on the entire circumference in a manner of covering the opening; a pressing member pressing the two sets of opposing linear edges toward the end portion of the opening in a state of leaving the four corners open; a groove formed in a receiving surface in a manner of surrounding the opening, the receiving surface receiving the end portion of the electrically insulating plate at the end portion of the opening; and an O-ring disposed in the groove, in at least one of the four corners, a surface of the end portion of the electrically insulating plate opposite to the receiving surface includes a contact surface and a separation surface, the contact surface contacting the receiving surface to cover the groove, the separation surface separating from the receiving surface at a position on an outer circumferential side than the contact surface, the pulse power module is connected to the discharge electrode via a plurality of feedthroughs embedded in the electrically insulating plate, the charger supplies a voltage to the pulse power module.

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