Laser device and method for manufacturing electronic device

Abstract

A laser device according to one aspect of the present disclosure comprises: a cavity into which laser gas is introduced; a pair of electrodes arranged in the cavity; a power supply that applies a voltage between the electrodes; a nozzle structure having an internal passage for receiving the laser gas and a slit communicating with the internal passage, wherein a flow of laser gas is generated between the electrodes by laser gas blown from the slit; a gas flow path having an intake port for sucking in the laser gas in the cavity, and guiding the laser gas sucked in from the intake port to the nozzle structure; and an air supply device that transports the laser gas to the internal passage of the nozzle structure through the gas flow path.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a laser device and an electronic device. Background Art

[0002] In recent years, in semiconductor exposure devices, as semiconductor integrated circuits become smaller and more highly integrated, there is a demand for improved resolution. Therefore, the wavelength of light emitted from an exposure light source has been shortened. For example, as a gas laser device for exposure, a KrF excimer laser device that outputs a laser with a wavelength of about 248nm and an ArF excimer laser device that outputs a laser with a wavelength of about 193nm are used.

[0003] The spectral line width of the natural oscillation light of the KrF excimer laser device and the ArF excimer laser device is relatively wide, about 350 to 400 pm. Therefore, when the projection lens is constructed using a material that allows ultraviolet light such as KrF and ArF lasers to pass through, chromatic aberration sometimes occurs. As a result, the resolution may be reduced. Therefore, it is necessary to narrow the spectral line width of the laser output from the gas laser device to a level where chromatic aberration can be ignored. Therefore, in order to narrow the spectral line width, a narrowing module (Line Narrow Module: LNM) containing narrowing elements (etalon, grating, etc.) is sometimes provided in the laser resonator of the gas laser device. Hereinafter, a gas laser device with a narrowed spectral line width is referred to as a narrowed gas laser device.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: U.S. Patent No. 6914919

[0007] Patent Document 2: Japanese Patent Application Publication No. 2007-208183 Summary of the invention

[0008] A laser device according to one aspect of the present disclosure comprises: a cavity into which laser gas is introduced; a pair of electrodes arranged in the cavity; a power supply that applies a voltage between the electrodes; a nozzle structure having an internal passage for receiving the laser gas and a slit communicating with the internal passage, wherein a flow of laser gas is generated between the electrodes by the laser gas blown out from the slit; a gas flow path having an intake port for sucking in the laser gas in the cavity, and guiding the laser gas sucked in from the intake port to the nozzle structure; and an air supply device that transports the laser gas to the internal passage of the nozzle structure through the gas flow path.

[0009] Another aspect of the present disclosure provides a method for manufacturing an electronic device, comprising the following steps: generating a laser by a laser device, outputting the laser to an exposure device, exposing the laser on a photosensitive substrate in the exposure device to manufacture the electronic device, wherein the laser device comprises: a cavity into which a laser gas is introduced; a pair of electrodes arranged in the cavity; a power supply for applying a voltage between the electrodes; a nozzle structure having an internal passage for receiving the laser gas and a slit communicating with the internal passage, wherein a flow of laser gas is generated between the electrodes by the laser gas blown from the slit; a gas flow path having an inlet for sucking in the laser gas in the cavity, and guiding the laser gas sucked in from the inlet to the nozzle structure; and an air supply device for conveying the laser gas to the internal passage of the nozzle structure through the gas flow path. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Hereinafter, several embodiments of the present disclosure will be described as simple examples with reference to the accompanying drawings.

[0011] Figure 1 A configuration example of a laser device according to a comparative example is schematically shown.

[0012] Figure 2 yes Figure 1 A cross-sectional view of the cavity taken along line 2-2 is shown.

[0013] Figure 3 A configuration example of the laser device according to the first embodiment is schematically shown.

[0014] Figure 4 This is an enlarged view schematically showing the discharge portion and the ring in the cavity.

[0015] Figure 5 yes Figure 4 Cross-sectional view at line 5-5 in FIG.

[0016] Figure 6 This is a schematic diagram showing the operating principle of the ring.

[0017] Figure 7 This is a front view when the ring is viewed from the downstream side toward the upstream side of the airflow.

[0018] Figure 8 The structure of the laser device according to the second embodiment is shown as an example.

[0019] Fig. 9 An example of the arrangement structure of a motor to which the magnetic coupling method is applied is schematically shown.

[0020] Fig.10 An example of the arrangement structure of a motor to which the magnetic bearing method is applied is schematically shown.

[0021] Fig.11 A configuration example of a laser device according to a third embodiment is schematically shown.

[0022] Fig.12 The flow of gas in the vicinity of the discharge portion and the ring in the chamber of the third embodiment is schematically shown.

[0023] Fig.13 The structure of the laser device according to the fourth embodiment is schematically shown.

[0024] Fig.14 This is an enlarged view schematically showing the first ring, the discharge portion, and the second ring in the chamber of the fourth embodiment.

[0025] Fig.15 The structure of a laser device according to a modified example of the fourth embodiment is schematically shown.

[0026] Fig.16 An example of the structure of a discharge portion in a cavity and a slit strip in a laser device according to a fifth embodiment is schematically shown.

[0027] Fig.17 yes Fig.16 A cross-sectional view taken along line 17-17 in FIG.

[0028] Fig.18 The structure of the periphery of the discharge portion in the cavity of the laser device according to the sixth embodiment is schematically shown.

[0029] Fig.19 A configuration example of an exposure device is schematically shown. DETAILED DESCRIPTION

[0030] -Table of contents-

[0031] 1. Overview of Laser Device of Comparative Example

[0032] 1.1 Structure

[0033] 1.2 Action

[0034] 1.3 Topics

[0035] 2. Implementation Method 1

[0036] 2.1 Structure

[0037] 2.1.1 Overall structure

[0038] 2.1.2 Structure of the discharge part and ring

[0039] 2.2 Action

[0040] 2.2.1 Ring operation principle

[0041] 2.2.2 Specific numerical examples

[0042] 2.3 Effects

[0043] 3. Implementation Method 2

[0044] 3.1 Structure

[0045] 3.2 Action

[0046] 3.3 Effects

[0047] 4. Implementation Method 3

[0048] 4.1 Structure

[0049] 4.2 Action

[0050] 4.3 Effects

[0051] 5. Implementation Method 4

[0052] 5.1 Structure

[0053] 5.2 Action

[0054] 5.3 Effects

[0055] 5.4 Variations

[0056] 6. Implementation Method 5

[0057] 6.1 Structure

[0058] 6.2 Action

[0059] 6.3 Effects

[0060] 6.4 Variations

[0061] 7. Implementation Method 6

[0062] 7.1 Structure

[0063] 7.2 Action

[0064] 7.3 Effects

[0065] 8. Method for manufacturing electronic devices

[0066] 9. Others

[0067] Below, the embodiments of the present disclosure are described in detail with reference to the accompanying drawings. The embodiments described below show several examples of the present disclosure and do not limit the content of the present disclosure. In addition, the structures and actions described in each embodiment are not necessarily all necessary for the structures and actions of the present disclosure. In addition, the same reference numerals are marked on the same structural elements and repeated descriptions are omitted.

[0068] 1. Overview of Laser Device of Comparative Example

[0069] 1.1 Structure

[0070] Figure 1A configuration example of a laser device 10 according to a comparative example is schematically shown. Figure 2 yes Figure 1 The cross-sectional view at line 2-2 of the cavity 12 is shown. The comparative examples disclosed in the present invention are methods that the applicant recognizes are only known to the applicant, and are not known examples acknowledged by the applicant himself.

[0071] The laser device 10 includes a cavity 12 and a power supply 14. The cavity 12 includes a pair of electrodes 16a, 16b, an electrical insulating member 18, a corotron 20, a cross-flow fan 30, a motor 32, a magnetic bearing 34, a heat sink 38 and two windows 41,42.

[0072] The cavity 12 is connected to a laser gas supply device and a laser gas exhaust device (not shown). Laser gas is introduced into the cavity 12 via the laser gas supply device. The laser gas may include, for example, argon (Ar) or krypton (Kr) as a rare gas, fluorine (F2) as a halogen gas, neon (Ne) or helium (He) as a buffer gas, or a mixed gas thereof. The laser gas supply device includes a valve (not shown) and a flow control valve (not shown). The laser gas supply device is connected to a gas cylinder (not shown). The laser gas exhaust device may also include a valve and an exhaust pump (not shown).

[0073] The cavity 12 is arranged on the optical path of the laser resonator (not shown). The laser resonator is configured to include, for example, a narrowband module (LNM) and an output coupling mirror. The narrowband module includes a grating, a prism, and a rotating stage for rotating the prism. The prism is arranged so that the beam of laser light output from the cavity 12 is magnified by the prism and incident on the grating at a predetermined angle. The rotating stage is arranged so that when the prism rotates, the incident angle of the beam relative to the grating changes. The grating is Littrow-configured so that the incident angle and the diffraction angle of the beam become the same angle.

[0074] The output coupling mirror may be a partial reflective mirror coated with a multilayer film that reflects a portion of the laser light generated in the cavity 12 and transmits another portion. The cavity 12 is configured so that a discharge region of electrodes 16a and 16b is disposed on the optical path of the laser resonator. The electrode 16a is a cathode electrode, and the electrode 16b is an anode electrode.

[0075] The power supply 14 may be, for example, a pulse power module (PPM). The power supply 14 is connected to the electrode 16a via a feed channel of an electrically insulating component 18. The electrode 16b is connected to the grounded cavity 12. The power supply 14 includes a switch (not shown) and a charging capacitor (not shown) for generating a discharge 44 between the electrodes 16a, 16b. The charging capacitor is connected to a charger (not shown). The switch and the charger are connected to a laser control device (not shown).

[0076] The corotron 20 is extended and arranged substantially parallel to the electrode 16b. The corotron 20 includes a rod-shaped corona inner electrode 21 as an internal conductor and a tubular outer dielectric 22 covering the outer periphery of the corona inner electrode 21. The corona inner electrode 21 is connected to the high voltage side of a high voltage power supply (not shown). A corona outer electrode 23 is connected to the outer side of the outer dielectric 22. The outer dielectric 22 is grounded via the corona outer electrode 23.

[0077] The motor 32 is a power source of the cross flow fan 30 . The rotation shaft of the cross flow fan 30 is supported by the chamber 12 via a magnetic bearing 34 .

[0078] 1.2 Action

[0079] The laser gas circulates in the chamber 12 by a cross flow fan 30 disposed in the chamber 12 .

[0080] The laser control device receives various target data and light emission trigger signals from the control device of the exposure device (not shown). The target data is, for example, the target pulse energy Et, the target wavelength λt, the target line width Δλt, etc. The charging voltage is set to the charger in such a way that the pulse energy of the output laser becomes the target pulse energy Et, and the switch in the power supply 14 is operated synchronously with the light emission trigger signal. The switch is operated, thereby, a high voltage can be applied between the corona inner electrode 21 and the corona outer electrode 23, and between the electrodes 16a and 16b.

[0081] Thus, first, corona discharge is generated in the preliminary ionization discharge section including the corona tube 20 and the corona outer electrode 23, and UV (ultraviolet) light is generated. When the generated UV light is irradiated on the laser gas between the electrodes 16a and 16b for the main discharge, the laser gas between the electrodes 16a and 16b can be pre-ionized. Then, discharge 44 is generated between the electrodes 16a and 16b, thereby exciting the laser gas. The light emitted from the excited laser gas reciprocates in the laser resonator formed by the output coupling mirror and the narrowband module, thereby becoming laser oscillation. The laser light reciprocating in the laser resonator is narrowbanded by the prism and the grating, and a part of it is emitted from the output coupling mirror. The discharge product DP containing metal dust is generated in the cavity 12 by the discharge 44.

[0082] In this specification, the space between the electrodes 16a and 16b where the discharge 44 is generated is referred to as a "discharge space", and the area around the electrodes 16a and 16b including the electrodes 16a and 16b and the discharge space is referred to as a "discharge portion". In addition, in this specification, unless otherwise specified, the description "between the electrodes" refers to the space between the electrodes 16a and 16b.

[0083] 1.3 Topics

[0084] The laser device 10 of the comparative example has the following problems.

[0085] [Problem 1] The density waves (sound waves) generated by the discharge 44 are reflected by the blades 31 of the cross flow fan 30 and return to the discharge space, whereby the energy is modulated, thereby deteriorating the energy stability.

[0086] [Question 2] The flow of gas generated by the cross flow fan 30 is modulated in accordance with the rotation of the blades 31. That is, the flow of gas is not an ideal continuous flow. Figure 2 The cross flow fan 30 in the discharge space has a modulation in the air flow in the gas path corresponding to the rotating blades 31. Figure 2 , an image of the acoustic wave ACW after being reflected by the blade 31 is illustrated.

[0087] [Problem 3] In order to generate the flow of gas throughout the chamber 12, the motor 32, the cross flow fan 30, and the magnetic bearing 34 are enlarged. Since these elements rotate at high speed, the vibration becomes larger. In addition, the enlargement of these elements increases the cost.

[0088] 2. Implementation Method 1

[0089] 2.1 Structure

[0090] 2.1.1 Overall structure

[0091] Figure 3 An example configuration of the laser device 100 according to the first embodiment is schematically shown. Figure 3 The structure shown is Figure 1 and Figure 2 The differences from the comparative example are described below. Figure 3 The laser device 100 shown in the figure is provided with a ring 50 with a slit in the chamber 12 instead of the cross flow fan 30. The ring 50 with a slit forms a flow of the laser gas. Figure 4 and Figure 5 Hereinafter, the laser gas may be simply referred to as "gas", and the flow of the laser gas may be referred to as "airflow" or "wind".

[0092] The ring 50 is a hollow annular (ring-shaped) structure, and the ring 50 has an internal passage 52 for receiving gas and a slit 54 that serves as a gas blowing outlet. "Annular" means a shape that can be understood as a "closed figure". A "closed figure" can also be said to be a "closed curve". The ring 50 of this example has a shape that can be understood as a roughly rectangular shape when viewed from the front. The ring 50 is a nozzle structure that receives gas in the annular internal passage 52 and blows gas out from the annular slit 54. The cross-sectional shape of the ring 50 is an airfoil shape like the wing of an airplane.

[0093] The slit 54 is provided on the inner peripheral surface of the ring 50. Figure 3 The gas is blown out in the right direction to form a gas flow in the discharge space.

[0094] Figure 3 The arrow Gf1 in FIG. 5 represents the flow of the gas blown out from the slit 54 of the ring 50. The arrow Gf2 represents the flow of the gas that does not pass through the ring 50, among the gas flows amplified by the gas blown out from the slit 54. The arrow Gf3 represents the flow of the gas that passes through the ring 50, among the gas flows amplified by the gas blown out from the slit 54.

[0095] The ring 50 is arranged at a position upstream of the discharge space relative to the flow of the gas flowing in the discharge space. A gas flow path 60 is provided outside the cavity 12. In addition, a gas flow path 61 communicating with the gas flow path 60 is arranged inside the cavity 12. The gas flow path 61 is connected to the ring 50. The gas flow paths 60 and 61 constitute a gas circulation path for returning the gas after passing through the discharge space to the internal passage 52 of the ring 50 again to circulate the gas.

[0096] The gas flow path 60 has an inlet 60A that serves as an inlet for the gas, and the inlet 60A is connected to the chamber 12. A dust filter 62 is disposed in the gas flow path 60. The dust filter 62 captures metal dust. In addition, a fan 64 and a motor 65 are disposed in the gas flow path 60. The motor 65 is a power source for rotating the fan 64. The motor 65 is driven to rotate the fan 64, thereby increasing the pressure on the downstream side in the gas flow path 60 and generating an airflow. The rotation of the fan 64 transports the gas toward the internal passage 52 of the ring 50.

[0097] The fan 64 and the motor 65 may also be arranged outside the chamber 12. Preferably, the motor 65 is a structure that is not exposed to the fluorine gas. In addition, other embodiments of the configuration structure of the motor 65 are described using Fig. 9 and Fig.10 This will be described later.

[0098] In addition, the structure for conveying gas toward the inner passage 52 of the ring 50 is not limited to the example using the fan 64 and the motor 65, and may also be as described later. Fig.16 A compressor is used as exemplified in .

[0099] The radiator 38 is disposed in the path of the gas flow. The radiator 38 can be disposed at any position as long as it is in the gas path for gas circulation. Figure 3 As shown, it is arranged inside the cavity 12. Figure 3 The heat sink 38 shown is disposed in the gas path between the electrodes 16a and 16b and the suction port 60A of the gas flow path 60. Alternatively, the heat sink 38 may be disposed in the gas flow path 60.

[0100] The laser gas contains fluorine gas, so the inner wall of the cavity 12 and the gas flow paths 60, 61 and other parts in contact with the laser gas are made of materials having fluorine resistance, or are subjected to surface treatment having fluorine resistance. Examples of materials having fluorine resistance include nickel (Ni), stainless steel (SUS), copper (Cu), etc. Examples of surface treatments having fluorine resistance include fluorine passivation treatments such as electroless nickel plating.

[0101] In addition, Figure 3 In the embodiment, a gas circulation path is formed by providing a gas flow path 60 outside the cavity 12, but the present invention is not limited to this structure, and a gas circulation path may be formed inside the cavity 12 so that the gas circulates inside the cavity 12. An example of a method of forming a gas circulation path inside the cavity 12 is to use Figure 8 This will be described later.

[0102] 2.1.2 Structure of the discharge part and ring

[0103] Figure 4 It is an enlarged view schematically showing the discharge portion and the ring 50 in the cavity 12 . Figure 5 yes Figure 4 The cross-sectional view at line 5-5 in FIG. Figure 4 yes Figure 5 For the sake of convenience, the cross-sectional view at line 4-4 in FIG. Figure 4 and Figure 5 As shown, a rectangular coordinate system of V axis, H axis and Z axis is defined. The V axis direction is the direction in which the electrodes 16a and 16b face each other, that is, the direction of the electrode interval EDv between the electrodes 16a and 16b ( Figure 4 The H-axis direction is the longitudinal direction of the electrodes 16a and 16b, that is, the direction of the electrode length ELh ( Figure 5 The Z-axis direction is the short side direction of the electrodes 16a and 16b ( Figure 4 The horizontal Figure 5 The traveling direction (gas flow direction) of the gas flowing between the electrodes 16a and 16b is set to the direction on the positive side of the Z axis. The Z axis direction is an example of the “first direction” in the present disclosure. The H axis direction is an example of the “second direction” in the present disclosure. The V axis direction is an example of the “third direction” in the present disclosure.

[0104] like Figure 4 As shown in FIG. 1 , the ring 50 is arranged at a position upstream of the electrodes 16a and 16b relative to the flow of the gas. The ring 50 has an annular slit 54 along the inner circumference of the ring 50. Figure 5As shown, when viewed from the Z-axis direction, the ring 50 has a substantially rectangular horizontally long shape. The “substantially rectangular” includes the shape of the four corners of the rectangle being changed into arc-shaped curved lines (rounded rectangle). The slit portion 54U corresponding to the upper side and the slit portion 54D corresponding to the lower side of the substantially rectangular annular slit 54 are arranged parallel to the H-axis direction. The opening width (slit width) of the slit 54 can be, for example, about several millimeters.

[0105] It is preferred that the slit length SLh in the H-axis direction of the ring 50 is the same as or longer than the discharge length DLh in the H-axis direction. That is, it is preferred to satisfy SLh≥DLh. The discharge length DLh is the length of the discharge space in the H-axis direction. The electrode interval EDv is the length of the discharge space in the V-direction. The ring 50 is made of an insulating material (dielectric) such as ceramics or resin.

[0106] In addition, if Figure 5 As shown in FIG. 1 , the slit 54 is arranged to enter the inner side of the electrode interval EDv. That is, the slit 54 is arranged in a space formed by extending the discharge space in the Z-axis direction. The slit height SHv in the V-axis direction of the ring 50 is set to obtain the required air volume and required flow rate described later. There is no particular limitation on the slit height SHv relative to the electrode interval EDv, but it is preferred that the slit height SHv is smaller than the electrode interval EDv.

[0107] In addition, the shape of the ring 50 is not limited to Figure 5 Such a substantially rectangular shape may be an elongated circle with its short side being an arc-shaped curve.

[0108] 2.2 Action

[0109] 2.2.1 Ring operation principle

[0110] Figure 6 1 is a schematic diagram showing the operating principle of the ring 50 . Figure 7 This is a front view of the ring 50 when viewed from the downstream side of the airflow toward the upstream side. Figure 6 and Figure 7 As shown, the gas blown out from the slit 54 flows along the inner wall of the ring 50. Due to the flow of the gas, the pressure inside the ring 50 is reduced, so the gas outside the ring 50 is taken in together and an airflow is formed. As a result, the flow rate of the wind flowing to the downstream side of the ring 50 is increased compared to the amount of gas blown out from the slit 54.

[0111] When the air volume of the gas blown out from the slit 54 is represented by Qs and the amplified air volume is represented by Qa, the amplified air volume Qa is represented by the following formula (1).

[0112] Qa=A×Qs (1)

[0113] The proportionality constant A in equation (1) is called the amplification factor.

[0114] Furthermore, the amplified air volume Qa is the sum of the air volume Qi passing through the inside of the ring 50, the air volume Qo drawn in from the outside of the ring 50, and the air volume Qs blown out from the slit 54, and is expressed by the following formula (2).

[0115] Qa=Qi+Qo+Qs (2)

[0116] Based on equations (1) and (2), the amplification factor A is expressed by the following equation (3).

[0117] A=(Qi+Qo+Qs) / Qs (3)

[0118] In addition, the air volume Qs blown out from the slit 54 is referred to as "slit blow-out volume".

[0119] 2.2.2 Specific numerical examples

[0120] In order to perform laser oscillation at a high repetition frequency in an excimer laser device, it is necessary to generate an air flow having a wind speed (gas flow rate) V (m / s) or higher represented by the following formula (4) between the electrodes 16 a and 16 b .

[0121] V=f×w (4)

[0122] In formula (4), f is the repetition frequency. The unit of f is Hertz [Hz]. w is the discharge width in the airflow direction. The unit of w is meter [m].

[0123] Formula (4) is equivalent to the calculation when the CR (Clearance Ratio) value is 1. In addition, the CR value is a value indicating how many times the gas in the discharge space is replaced between pulses. That is, the air volume Qa [m 3 / s] becomes the following formula (5).

[0124] Qa=f×w×discharge length DLh×electrode interval EDv (5)

[0125] Here, regarding the repetition frequency f [Hz], the discharge width w [m], the discharge length DLh [m], and the electrode interval EDv [m], specific values ​​are shown as follows, for example.

[0126] f=6000 [Hz], w=0.003 [m], DLh=0.55 [m], EDv=0.016 [m] When these exemplary values ​​are substituted into equations (4) and (5), the required minimum flow velocity Vmin and the required minimum flow rate Qamin are calculated as follows.

[0127] Required minimum flow rate Vmin = 6000 [Hz] × 0.003 [m] = 18 [m / s]

[0128] Necessary minimum flow rate Qamin = 6000 [Hz] × 0.003 [m] × 0.55 [m] × 0.016 [m] = 0.1584 [m 3 / s]

[0129] Parameters such as the slit height SHv, the slit length SLh, the capacity of the motor 65, the rotation speed of the fan 64, and the shape and arrangement of the ring 50 are determined so that the minimum required flow rate Qamin is satisfied and the amplification factor A becomes maximum.

[0130] 2.3 Effects

[0131] According to the laser device 100 of the first embodiment, compared with the laser device 10 of the comparative example, the fan 64 is located at a position that is not visible from the discharge portion, and therefore, it is possible to suppress deterioration of energy stability due to acoustic waves.

[0132] In addition, the air volume of the gas flow forcibly formed by using the fan 64 and the motor 65 may be only the slit blowing volume Qs. Figure 1 and Figure 2 The structure of the laser device 10 of the comparative example described in the description requires a cross-flow fan 30 and a motor 32 for circulating an air volume equivalent to Qi+Qo+Qs (=A×Qa). In contrast, in the air supply method based on the structure of embodiment 1, a slit blow-out amount Qs of 1 / A of the required minimum flow rate is sufficient, thereby achieving miniaturization and cost reduction of the structure including the fan 64 and the motor 65.

[0133] 3. Implementation Method 2

[0134] 3.1 Structure

[0135] Figure 8 An example of the structure of the laser device 102 according to the second embodiment is schematically shown. Figure 8 The structure shown is Figure 3 The differences are explained. Figure 3 In the embodiment, a method in which the gas flow path 60 is provided outside the chamber 12 is described. However, Figure 8 The laser device 102 shown is of a type in which the gas flow path 60 is not provided outside the chamber 12 , but a gas circulation path is formed inside the chamber 12 so that the gas circulates inside the chamber 12 .

[0136] That is, the gas flow path 61 disposed inside the chamber 12 has a suction port 61A for sucking the gas in the chamber 12 , and the dust filter 62 is disposed near the suction port 61A of the gas flow path 61 .

[0137] The fan 64 is arranged between the dust filter 62 and the ring 50 in the gas flow path 61. The motor 65 can also be arranged in the gas flow path 61, but Fig. 9 and Fig.10 As shown, it is preferably a structure that is arranged outside the chamber 12 and is not exposed to the fluorine gas.

[0138] Fig. 9 An example of the arrangement structure of the motor 65 to which the magnetic coupling method is applied is schematically shown. Fig. 9 The structure shown is a so-called input-output type magnetic coupling, in which a cylindrical driving side magnet 68 is arranged on the shaft of the motor 65, and a cylindrical passive side magnet 74 is arranged on the outside thereof. A partition wall 70 is arranged between the driving side magnet 68 and the passive side magnet 74. The partition wall 70 covers the periphery of the passive side magnet 74 in such a manner that the motor 65 and the driving side magnet 68 are not exposed to the laser gas LG containing fluorine gas. The motor 65 is arranged outside the cavity 12 with the partition wall 70 separated. A rotating plate 76 is fixed to the passive side magnet 74, and a shaft 77 of the rotating plate 76 is supported by a bearing 78 so as to be rotatable. The fan 64 is connected to the shaft 77 of the rotating plate 76.

[0139] Fig.10 An example of the configuration structure of the motor 65 using the magnetic bearing method is schematically shown. Fig.10 As shown, the motor 65 includes a rotor 81 and a stator 82. The shaft 66 of the motor 65 is rotatably supported by a magnetic bearing 90. The magnetic bearing 90 includes an inner ring magnet 91 and an outer ring magnet 92. The inner ring magnet 91 is fixed to the shaft 66.

[0140] The periphery of the shaft 66 including the rotor 81 and the inner ring magnet 91 is covered by the partition wall 70 , so that the stator 82 and the outer ring magnet 92 are not exposed to the fluorine gas. The fan 64 is connected to the shaft 66 .

[0141] 3.2 Action

[0142] When the laser device 102 of the second embodiment drives the motor 65 to rotate the fan 64, the laser gas LG in the cavity 12 is sucked into the gas flow path 61 from the suction port 61A of the gas flow path 61, and the laser gas LG is transported to the internal passage 52 of the ring 50 through the gas flow path 61 and blown out from the slit 54. Figure 6 Same. Figure 8 As shown, the laser gas LG having passed through the discharge space passes through the heat sink 38, and a part of it flows into the suction port 61A again. In this way, the laser gas LG circulates in the chamber 12. The other operations are the same as those in the first embodiment.

[0143] 3.3 Effects

[0144] According to Embodiment 2, as in Embodiment 1, it is possible to suppress the deterioration of energy stability due to acoustic waves. In addition, according to Embodiment 2, it is possible to achieve miniaturization and cost reduction compared to the comparative example. Furthermore, in Embodiment 2, compared to Embodiment 1, it is not necessary to provide the gas flow path 60 outside the cavity 12, and it is possible to achieve further miniaturization.

[0145] 4. Implementation Method 3

[0146] 4.1 Structure

[0147] Fig.11 An example of the structure of the laser device 103 according to the third embodiment is schematically shown. Fig.11 The structure shown is Figure 3 The differences are explained.

[0148] exist Figure 3 In the embodiment, the ring 50 is arranged at a position upstream of the electrodes 16a and 16b in the gas flow. Fig.11 In the laser device 103 shown in FIG. 1 , the ring 150 is arranged at a position downstream of the electrodes 16a and 16b in the gas flow. Figure 3 The ring 150 is the same as the ring 50 described in . The ring 150 is an example of the "nozzle structure" in the present disclosure.

[0149] 4.2 Action

[0150] Fig.11 The structure shown utilizes the suction of gas toward the ring 150 to generate a gas flow between the electrodes 16a, 16b. Fig.12 The flow of gas in the vicinity of the discharge portion and the ring 150 in Embodiment 3 is schematically shown. Fig.12 As shown, gas is blown out from the slit 54 of the ring 150, whereby the airflow coming out of the slit 54 draws in the surrounding gas and is amplified by A times. A portion of the air volume Qo drawn in from the outside of the ring 150 passes between the electrodes 16a and 16b, and the other portion does not pass between the electrodes 16a and 16b.

[0151] The air volume of the gas passing between the electrodes 16a and 16b is greater than the slit blow-out volume Qs. On the other hand, when compared with the structure of the first embodiment, the air volume Qo drawn in from the outside of the ring 150 that passes between the electrodes 16a and 16b is reduced, so the flow velocity between the electrodes 16a and 16b is reduced compared with the first embodiment.

[0152] 4.3 Effects

[0153] According to Embodiment 3, the airflow amplification efficiency is slightly lower than that of Embodiments 1 and 2, but the deterioration of energy stability due to sound waves can be suppressed compared to the comparative example, thereby achieving miniaturization and cost reduction.

[0154] 5. Implementation Method 4

[0155] 5.1 Structure

[0156] Fig.13 The structure of the laser device 104 according to the fourth embodiment is schematically shown. Fig.13 The structure shown is Figure 3 The differences are explained. Fig.13 The laser device 104 of the fourth embodiment shown has rings 151 and 152 arranged on both the upstream and downstream sides of the electrodes 16a and 16b with respect to the flow of gas passing between the electrodes 16a and 16b. The ring 151 arranged on the upstream side of the electrodes 16a and 16b with respect to the flow of gas is referred to as a "first ring 151", and the ring 152 arranged on the downstream side of the electrodes 16a and 16b is referred to as a "second ring 152".

[0157] The portion of the gas flow path 60 downstream of the fan 64 branches into two paths. One of the branched paths, namely the first branched gas flow path 63A, is connected to the first ring 151 , and the other branched path, namely the second branched gas flow path 63B, is connected to the second ring 152 .

[0158] Fig.14 FIG. 1 is an enlarged view schematically showing the first ring 151, the discharge portion, and the second ring 152 in the chamber 12 of the fourth embodiment. The structures of the first ring 151 and the second ring 152 can be the same as those of the embodiment 4. Figure 3 to Figure 7 The same ring 50 as described in .

[0159] The second ring 152 has an internal passage 56 and a slit 58. The first ring 151 is an example of a "first nozzle structure" in the present disclosure, and the second ring 152 is an example of a "second nozzle structure" in the present disclosure.

[0160] The upper slit portion 54U of the slit 54 of the first ring 151 (see Figure 5 ) is an example of the "third seam" in the present disclosure, and the lower seam portion 54D (refer to Figure 5 ) is an example of the "fourth seam" in the present disclosure. Similarly, the upper seam portion of the seam 58 of the second ring 152 is an example of the "fifth seam" in the present disclosure, and the lower seam portion is an example of the "sixth seam" in the present disclosure. Fig.14 As shown, it is preferable that the slit height of the slit 58 of the second ring 152 is configured to be larger than the slit height of the slit 54 of the first ring 151 .

[0161] 5.2 Action

[0162] like Fig.14 As shown, when gas is blown out from the slit 54 of the first ring 151 at a slit blowing volume Qs1, the surrounding gas is drawn in and the air volume is amplified. The amplified air volume Qa1 flows toward the downstream side of the first ring 151, and the amplified air volume Qa1 becomes the suction of the second ring 152.

[0163] The amplified air volume Qa1 is the sum of the air volume Qi1 passing through the inside of the first ring 151, the air volume Qo1 drawn in from the outside of the first ring 151, and the air volume Qs1 blown out from the slit 54, and is expressed by the following equation (6).

[0164] Qa1=Qi1+Qo1+Qs1 (6)

[0165] 5.3 Effects

[0166] When the ring 50 is provided in the cavity 12, the electrode interval EDv of several tens of mm and other structures cause a large pressure loss, and sometimes the necessary flow rate cannot be obtained between the electrodes 16a and 16b, and sometimes the ideal amplification factor A cannot be obtained.

[0167] In order to solve this problem, it is considered to use a method of increasing the rotation speed of the fan 64 and the motor 65 at a lower magnification, or to use Fig.14 This structure shown.

[0168] exist Fig.14 In the fourth embodiment shown, the first ring 151 and the second ring 152 are arranged upstream and downstream of the electrodes 16a and 16b, and the discharge of the first ring 151 becomes the suction of the second ring 152. That is, the operation of the first ring 151 and the second ring 152 reduces the pressure loss between the electrodes 16a and 16b, so that the gas flows smoothly, resulting in an increase in the gas flow rate and the gas flow rate between the electrodes 16a and 16b.

[0169] 5.4 Variations

[0170] Fig.15 The structure of a laser device 105 according to a modified example of the fourth embodiment is schematically shown. Fig.15 The structure shown is Fig.13 The differences are explained.

[0171] The laser device 105 has a first gas flow path 160 connected to the first ring 151 and a second gas flow path 170 connected to the second ring 152, and dust filters 162, 172, fans 164, 174 and motors 165, 175 are arranged in each flow path. The first gas flow path 160 and the second gas flow path 170 can be branch pipelines (branch pipes) branched from the main pipeline 60B. The suction port 60A of the main pipeline 60B is connected to the gas outlet 12B of the chamber 12. The main pipeline 60B can be interpreted as a part of the first gas flow path 160, and can also be interpreted as a part of the second gas flow path 170.

[0172] The structure including the first gas flow path 160, the dust filter 162, the fan 164 and the motor 165 can be Figure 3 The structure including the gas flow path 60, the dust filter 62, the fan 64 and the motor 65 shown in FIG. 1 is the same as that shown in FIG. 1 . In addition, the structure including the second gas flow path 170, the dust filter 172, the fan 174 and the motor 175 may be the same as that shown in FIG. Fig.11 The structure shown including the gas flow path 60, dust filter 62, fan 64 and motor 65 is the same.

[0173] 6. Implementation Method 5

[0174] 6.1 Structure

[0175] Fig.16 An example of the structure of the discharge portion in the cavity and the slit bars 180 and 190 in the laser device according to the fifth embodiment is schematically shown. Fig.17 yes Fig.16 The cross-sectional view at line 17-17 in FIG. Fig.16 and Fig.17 The structure of the fifth embodiment shown will be described with respect to the differences from the first embodiment.

[0176] In the fifth embodiment, the ring 50 is replaced with strips 180 and 190 with slits. The pair of strips 180 and 190 corresponds to Figure 4 and Figure 5 The structure of the elements of the long side portion of the ring 50 described in the figure arranged parallel to the electrodes 16a and 16b. The strips 180 and 190 are respectively hollow strip-shaped (rod-shaped) structures. That is, the strip 180 has an internal passage 183 for receiving gas and a slit 184 that functions as a gas outlet. The strip 180 is arranged near the electrode 16a that serves as a cathode electrode. The strip 190 has an internal passage 193 for receiving gas and a slit 194 that functions as a gas outlet. The strip 190 is arranged near the electrode 16b that serves as an anode electrode.

[0177] The two strips 180 and 190 are arranged in parallel with the electrodes 16a and 16b, and the strips 180 and 190 are arranged opposite to each other so that the slits 184 and 194 face each other. The strips 180 and 190 are examples of "nozzle structures" in the present disclosure. The slit 184 is an example of "first slit" in the present disclosure, and the slit 194 is an example of "second slit" in the present disclosure.

[0178] In Embodiment 5, compressors 210 and 220 are used instead of the blower including the fan 64 and the motor 65. The compressors 210 and 220 may be turbo compressors. The compressors 210 and 220 are examples of "blowers" in the present disclosure.

[0179] The compressor 210 is connected to the bar 180 via the gas flow path 212. Similarly, the compressor 220 is connected to the bar 190 via the gas flow path 222. The gas flow paths 212 and 222 are respectively designed to increase the pressure to the maximum extent, and therefore, the radiators 214 and 224 and the dust filters 216 and 226 are preferably arranged on the primary side of the compressors 210 and 220.

[0180] 6.2 Action

[0181] The compressors 210 and 220 generate pressure, and the pressure blows out gas from the slits 184 and 194. The gas blown out from the slits 184 and 194 passes between the electrodes 16a and 16b, and returns to the primary side of the compressors 210 and 220 through a gas path (not shown).

[0182] 6.3 Effects

[0183] According to Embodiment 5, by using compressors 210 and 220 that pressurize and send gas, the pressure at the slits 184 and 194 can be set higher than that of a fan, a blower, or other air-sending device. Therefore, more gas can be blown out from the slits 184 and 194, and as a result, more gas can flow between the electrodes 16a and 16b at a high speed.

[0184] 6.4 Variations

[0185] The ring 50 may be used instead of the bars 180 and 190. In this case, either the compressors 210 and 220 may be omitted. The device for sending gas to the bars 180 and 190 is not limited to the compressors 210 and 220, but may be a blower such as a fan or a blower.

[0186] 7. Implementation Method 6

[0187] 7.1 Structure

[0188] Fig.18The structure around the discharge portion in the cavity of the laser device of Embodiment 6 is schematically shown. In the laser device of Embodiment 6, slit strips 240 and 250 are arranged on the side portions on the upstream side of each of the electrodes 16a and 16b, and slit strips 260 and 270 are arranged on the side portions on the downstream side of each of the electrodes 16a and 16b.

[0189] A corona inner electrode 281 is disposed inside the strip 240. Similarly, corona inner electrodes 282, 283, 284 are disposed inside each of the strips 250, 260, 270. Other structures associated with each of the strips 240, 250, 260, 270 may be the same as those described above. Fig.16 The strips 180 and 190 described above are the same. The strips 240, 250, 260 and 270 are made of dielectric materials.

[0190] Corona outer electrodes 291 and 292 are attached to the side surfaces of the electrodes 16a and 16b on the upstream side, respectively. Similarly, corona outer electrodes 293 and 294 are attached to the side surfaces of the electrodes 16a and 16b on the downstream side, respectively.

[0191] Regarding the strip 240, the dielectric strip 240 is sandwiched between the corona outer electrode 291 and the corona inner electrode 281 inside the strip 240. The other strips 250, 260, and 270 are similarly sandwiched between the corona outer electrode 292 and the corona inner electrode 282, the strip 260 is sandwiched between the corona outer electrode 293 and the corona inner electrode 283, and the strip 270 is sandwiched between the corona outer electrode 294 and the corona inner electrode 284. Fig.18 , a structure using corona outer electrodes 291, 292, 293, 294 is shown, however, the corona outer electrodes 291, 292, 293, 294 may not be provided, and dielectric strips 240, 250, 260, 270 may be respectively arranged in contact with the corresponding electrodes 16a, 16b.

[0192] In addition, Fig.18 In the description, there are four corona outer electrodes and four corona inner electrodes, but the invention is not limited thereto, and the number of corona outer electrodes and corona inner electrodes may be one to three, respectively. Fig.18 The structure of the strips 240, 250, 260, 270 shown can be replaced by Fig.13 and Fig.14 The structure of the rings 151 and 152 described in FIG.

[0193] 7.2 Action

[0194] The strips 240 and 250 disposed on the upstream side of the electrodes 16a and 16b play the same role as Fig.14 The strips 260 and 270 arranged on the downstream side of the electrodes 16a and 16b play the same role as the ring 151 on the upstream side described in the above. Fig.14 The ring 152 on the downstream side described in has the same function.

[0195] The strips 240, 250, 260, 270 blow out gas from the respective slits 244, 254, 264, 274, draw in the surrounding gas, and increase the airflow.

[0196] The corona inner electrodes 281, 282, 283, 284 are applied with voltage from the outside, so that a predetermined potential difference is obtained between the corona inner electrodes 281, 282, 283, 284 and the corona outer electrodes 291, 292, 293, 294 opposed to each other. As a unit for applying voltage, a voltage dividing capacitor can be used to divide the voltage between the electrodes 16a, 16b of the cathode and the anode. When the potential difference between the inner and outer electrodes becomes more than a certain value, a corona discharge (dielectric barrier discharge) is generated, and the discharge light irradiates between the electrodes 16a, 16b to ionize the gas.

[0197] The strips 240, 250, 260, and 270 are examples of the "nozzle structure" in the present disclosure. The slit 244 of the strip 240 and the slit 264 of the strip 260 are examples of the "first slit" in the present disclosure, and the slit 254 of the strip 250 and the slit 274 of the strip 270 are examples of the "second slit" in the present disclosure. Each strip 240 and the strip 250 or a combination thereof is an example of the "first nozzle structure" in the present disclosure, and each strip 260 and the strip 270 or a combination thereof is an example of the "second nozzle structure" in the present disclosure.

[0198] The slit 244 of the strip 240 is an example of the "third slit" of the present disclosure, the slit 254 of the strip 250 is an example of the "fourth slit" of the present disclosure, the slit 264 of the strip 260 is an example of the "fifth slit" of the present disclosure, and the slit 274 of the strip 270 is an example of the "sixth slit" of the present disclosure.

[0199] 7.3 Effects

[0200] According to Embodiment 6, the bars 240, 250, 260, 270 or the rings replacing the bars that form the flow of the gas supplied between the electrodes 16a and 16b can also serve as the unit for corona preliminary ionization, and a compact device can be designed. In addition, according to Embodiment 6, the corona luminescence is not blocked by the bars 240, 250, 260, 270 and the rings, and therefore, preliminary ionization can be performed strongly.

[0201] 8. Method for manufacturing electronic devices

[0202] Fig.19The structure example of the exposure device 400 is schematically shown. The exposure device 400 includes an illumination optical system 444 and a projection optical system 450. The illumination optical system 444 illuminates the mask pattern of the mask (not shown) arranged on the mask stage RT by the laser light incident from the laser device 100. The projection optical system 450 performs reduced projection of the laser light transmitted through the mask so as to form an image on the workpiece (not shown) arranged on the workpiece stage WT. The workpiece is a photosensitive substrate such as a semiconductor wafer coated with a resist.

[0203] The exposure device 400 moves the mask stage RT and the work stage WT synchronously and in parallel, thereby exposing the workpiece to the laser reflecting the mask pattern. After the mask pattern is transferred to the semiconductor wafer through the above exposure process, a semiconductor device can be manufactured through multiple processes. The semiconductor device is an example of an "electronic device" in the present disclosure.

[0204] Fig.19 The laser device 100 in the embodiment may be the laser device described as Embodiments 2 to 6 or the like.

[0205] 9. Others

[0206] The above description is not limiting but simply illustrative. Therefore, those skilled in the art will appreciate that changes can be made to the embodiments of the present disclosure without departing from the claims. In addition, those skilled in the art will appreciate that the embodiments of the present disclosure can be used in combination.

[0207] Unless explicitly stated otherwise, the terms used in this specification and claims as a whole should be interpreted as "non-limiting" terms. For example, terms such as "include", "all", "have", and "have" should be interpreted as "excluding the existence of structural elements other than the structural elements to be recorded". In addition, the modifier "one" should be interpreted as meaning "at least one" or "one or more". In addition, 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". Furthermore, it should be interpreted as also including combinations of them and parts other than "A", "B", and "C".

Claims

1. A laser device, comprising: a cavity into which the laser gas is introduced; a pair of electrodes disposed in the cavity; a power source for applying a voltage between the electrodes; a nozzle structure having an internal passage for receiving the laser gas and a slit communicating with the internal passage, wherein the laser gas blown out from the slit generates a flow of the laser gas between the electrodes; a gas flow path having a suction port for sucking the laser gas in the chamber, and guiding the laser gas sucked from the suction port to the nozzle structure; and The air supply device supplies the laser gas to the internal passage of the nozzle structure through the gas flow path.

2. The laser device according to claim 1, wherein: At least a portion of the slit is disposed in a space formed by extending a discharge space between the electrodes in a first direction, which is a short-side direction of the electrodes.

3. The laser device according to claim 2, wherein: At least a portion of the slit is parallel to the second direction which is the longitudinal direction of the electrode.

4. The laser device according to claim 3, wherein: The seam has a first seam and a second seam, The first slit and the second slit are arranged to be separated in a third direction in which the pair of electrodes face each other, and a distance between the first slit and the second slit in the third direction is smaller than a distance between the electrodes.

5. The laser device according to claim 3, wherein: The length of the slit in the second direction is greater than the length of the electrode in the second direction.

6. The laser device according to claim 1, wherein: The nozzle structure is arranged at an upstream side of the electrodes with respect to the flow of the laser gas flowing between the electrodes.

7. The laser device according to claim 1, wherein: The nozzle structure comprises a first nozzle structure and a second nozzle structure. The first nozzle structure is arranged at an upstream side of the electrodes relative to the flow of the laser gas flowing between the electrodes. The second nozzle structure is arranged on the downstream side of the electrodes with respect to the flow of the laser gas flowing between the electrodes.

8. The laser device according to claim 7, wherein: The first nozzle structure has a third slit and a fourth slit as the slits, The second nozzle structure has a fifth slit and a sixth slit as the slits, The third slit and the fourth slit are arranged to be separated in a third direction, which is a direction in which the pair of electrodes face each other. The fifth slit and the sixth slit are arranged to be separated in the third direction, The interval between the fifth slit and the sixth slit in the third direction is larger than the interval between the third slit and the fourth slit in the third direction.

9. The laser device according to claim 1, wherein: The nozzle structure is annular, and the slit is provided on the inner peripheral surface of the annular nozzle structure.

10. The laser device according to claim 1, wherein: The nozzle structure is in a strip shape.

11. The laser device according to claim 1, wherein: The laser device further includes a dust filter disposed on a path through which the laser gas flows.

12. The laser device according to claim 1, wherein: The laser device also has: a corona outer electrode connected to the electrode and the nozzle structure; and The corona inner electrode is arranged inside the nozzle structure.

13. The laser device according to claim 1, wherein: The nozzle structure is made of insulating material.

14. The laser device according to claim 1, wherein: The air supply device includes a fan and a motor that rotates the fan.

15. The laser device according to claim 1, wherein: The air supply device includes a compressor.

16. The laser device according to claim 1, wherein: The laser gas contains fluorine.

17. The laser device according to claim 1, wherein: At least a portion of the gas flow path is disposed outside the chamber.

18. The laser device according to claim 1, wherein: The gas flow path is disposed in the cavity, The laser gas circulates within the chamber.

19. A method for manufacturing an electronic device, comprising the following steps: The laser is generated by a laser device, outputting the laser to an exposure device, exposing the laser on a photosensitive substrate in the exposure device to manufacture an electronic device, The laser device has: a cavity into which the laser gas is introduced; a pair of electrodes disposed in the cavity; a power source for applying a voltage between the electrodes; a nozzle structure having an internal passage for receiving the laser gas and a slit communicating with the internal passage, wherein the laser gas blown out from the slit generates a flow of the laser gas between the electrodes; a gas flow path having a suction port for sucking the laser gas in the chamber, and guiding the laser gas sucked from the suction port to the nozzle structure; and The air supply device supplies the laser gas to the internal passage of the nozzle structure through the gas flow path.

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