阅读说明：本技术 激光腔、密封部件的制造方法和电子器件的制造方法
(Laser cavity, method for manufacturing sealing member, and method for manufacturing electronic device
) 是由 三木正晴 于 2018-04-23 设计创作，主要内容包括：准分子激光装置的激光腔具有：容器,其包含第1部件和第2部件,在内部收纳激光气体；以及密封部件,其被配置于所述第1部件与所述第2部件的对置的2个密封面之间,所述密封部件的激光气体侧的表面由氟橡胶构成,所述密封部件的大气侧的表面由抑制大气透过的膜构成。(The laser cavity of the excimer laser device has: a container which includes a 1 st member and a 2 nd member and contains laser gas therein; and a seal member disposed between 2 opposed seal surfaces of the 1 st member and the 2 nd member, a surface of the seal member on a laser gas side being made of a fluororubber, and a surface of the seal member on an atmosphere side being made of a film that suppresses atmospheric permeation.)
1. A laser cavity of an excimer laser apparatus, wherein the laser cavity has:
a container which includes a 1 st member and a 2 nd member and contains laser gas therein; and
a seal member disposed between 2 opposed seal surfaces of the 1 st member and the 2 nd member,
the surface of the sealing member on the laser gas side is made of fluororubber,
the surface of the sealing member on the atmosphere side is formed of a film that suppresses permeation of the atmosphere.
2. A laser cavity according to claim 1,
the surfaces of the seal member contacting the 2 seal surfaces are each made of fluororubber.
3. A laser cavity according to claim 1,
the film comprises fluorine-containing diamond-like carbon.
4. A laser cavity according to claim 1,
the film comprises Al2O3、SiO2And TiO.
5. A laser cavity according to claim 1,
the film has a thickness of 0.1 μm or more and 0.3 μm or less.
6. A laser cavity according to claim 1,
the film comprises a plurality of layers that inhibit atmospheric transmission.
7. A laser cavity according to claim 6,
the plurality of layers includes a 1 st layer and a 2 nd layer located on the atmosphere side of the 1 st layer,
the area of the 2 nd layer is smaller than the area of the 1 st layer.
8. A laser cavity according to claim 6,
the plurality of layers includes a 1 st layer and a 2 nd layer located on the atmosphere side of the 1 st layer,
the thickness of the 2 nd layer is less than the thickness of the 1 st layer.
9. A laser cavity according to claim 1,
the 1 st part is made of metal,
the 2 nd member is made of ceramic.
10. A laser cavity according to claim 1,
the 1 st part is made of metal,
the 2 nd member includes an optical element through which laser light passes.
11. A laser cavity according to claim 1,
the 1 st member and the 2 nd member are both made of metal.
12. A method for manufacturing an annular seal member having a film on a part of a surface thereof, the method comprising:
a first step of fitting an annular member constituting the seal member on an outer periphery of a first jig 1;
a 2 nd step of clamping the annular member by a 2 nd jig and a 3 rd jig so that an outer peripheral surface of the annular member is exposed between the 2 nd jig and the 3 rd jig, the 2 nd jig being disposed on an outer periphery of the 1 st jig, the 3 rd jig being disposed on an outer periphery of the 1 st jig, and the interval between the 2 nd jig and the 3 rd jig being changeable by moving in an axial direction of the 1 st jig; and
and a 3 rd step of forming the film on the outer peripheral surface of the annular member in a state where the outer peripheral surface of the sealing member is exposed between the 2 nd jig and the 3 rd jig.
13. The manufacturing method of a seal member according to claim 12,
the 2 nd step includes the steps of: adjusting a gap between the 2 nd jig and the 3 rd jig in a state where the annular member is pressed in the axial direction, thereby adjusting a dimension of the annular member in the axial direction.
14. The manufacturing method of a seal member according to claim 12,
the outer peripheral surface of the 1 st jig has a taper portion whose diameter varies along the axial direction,
the 2 nd jig is configured to be movable in an axial direction of the 1 st jig,
the step 1 includes a step of bringing an inner peripheral surface of the annular member into contact with the tapered portion,
the 2 nd step includes the steps of: and adjusting the size of the inner diameter of the annular member by moving at least one of the 2 nd jig and the 3 rd jig in the axial direction.
15. The manufacturing method of a seal member according to claim 12,
the 3 rd step includes the following steps: forming a 1 st layer included in the film, and then forming a 2 nd layer included in the film at a position further outside than the 1 st layer,
after the 1 st layer is formed and before the 2 nd layer is formed, the dimension of the annular member in the axial direction is changed by changing the interval between the 2 nd jig and the 3 rd jig.
16. The manufacturing method of a seal member according to claim 12,
the outer peripheral surface of the 1 st jig has a taper portion whose diameter varies along the axial direction,
the 2 nd jig is configured to be movable in an axial direction of the 1 st jig,
the step 1 includes a step of bringing an inner peripheral surface of the annular member into contact with the tapered portion,
the 3 rd step includes the following steps: forming a 1 st layer included in the film, and then forming a 2 nd layer included in the film at a position further outside than the 1 st layer,
after the 1 st layer is formed and before the 2 nd layer is formed, at least one of the 2 nd jig and the 3 rd jig is moved in the axial direction, thereby changing the dimension of the inner diameter of the annular member.
17. A method for manufacturing an electronic device, comprising the steps of:
the laser light is generated by an excimer laser apparatus comprising a laser cavity,
the laser light is output to an exposure device,
exposing the laser light on a photosensitive substrate in the exposure apparatus to manufacture an electronic device,
wherein the content of the first and second substances,
the laser cavity has:
a container which includes a 1 st member and a 2 nd member and contains laser gas therein; and
a seal member disposed between 2 opposed seal surfaces of the 1 st member and the 2 nd member,
the surface of the sealing member on the laser gas side is made of fluororubber,
the surface of the sealing member on the atmosphere side is formed of a film that suppresses permeation of the atmosphere.
Technical Field
The present disclosure relates to a laser cavity, a method of manufacturing a sealing member and a method of manufacturing an electronic device.
Background
With the miniaturization and high integration of semiconductor integrated circuits, the improvement of resolution is required in semiconductor exposure apparatuses. Hereinafter, the semiconductor exposure apparatus is simply referred to as "exposure apparatus". Therefore, the wavelength of light output from the exposure light source has been reduced. A gas laser apparatus was used as the exposure light source instead of the conventional mercury lamp. Currently, as a gas laser apparatus for exposure, a KrF excimer laser apparatus that outputs ultraviolet rays having a wavelength of 248nm and an ArF excimer laser apparatus that outputs ultraviolet rays having a wavelength of 193nm are used.
As a current exposure technique, the following immersion exposure has been put into practical use: a gap between a projection lens and a wafer on the exposure apparatus side is filled with a liquid, and the wavelength of the appearance of an exposure light source is shortened by changing the refractive index of the gap. When liquid immersion exposure is performed using an ArF excimer laser apparatus as an exposure light source, ultraviolet light having a wavelength of 134nm in water is irradiated to a wafer. This technique is called ArF immersion exposure. ArF immersion exposure is also known as ArF immersion lithography.
Since the spectral line width in natural oscillation of KrF or ArF excimer laser devices is as wide as about 350 to 400pm, the laser light (ultraviolet light) projected onto the wafer by the projection lens on the exposure device side being reduced in size causes chromatic aberration, and the resolution is lowered. Therefore, it is necessary to narrow the line width of the laser light output from the gas laser device to such an extent that chromatic aberration can be ignored. The spectral line width is also referred to as spectral width. Therefore, a Narrow-band Module (Line Narrow Module) having a Narrow-band element is provided in a laser resonator of the gas laser device, and the Narrow-band Module is used to Narrow the spectral width. The narrow-band element may be an etalon, a grating, or the like. A laser device in which such a spectral width is narrowed is referred to as a narrowed laser device.
Disclosure of Invention
The laser cavity of the excimer laser device of 1 viewpoint of the present disclosure has: a container which includes a 1 st member and a 2 nd member and contains laser gas therein; and a sealing member disposed between 2 facing sealing surfaces of the 1 st member and the 2 nd member, wherein a surface of the sealing member on the laser gas side is made of a fluororubber, and a surface of the sealing member on the atmosphere side is made of a film that suppresses atmospheric permeation.
A method for manufacturing a seal member according to 1 aspect of the present disclosure is a method for manufacturing an annular seal member having a film on a part of a surface thereof, the method including: a first step of fitting an annular member constituting a seal member on an outer periphery of a first jig 1; a 2 nd step of clamping the annular member by a 2 nd jig and a 3 rd jig so that the outer peripheral surface of the annular member is exposed between the 2 nd jig and the 3 rd jig, the 2 nd jig being disposed on the outer periphery of the 1 st jig, the 3 rd jig being disposed on the outer periphery of the 1 st jig, and the interval between the 2 nd jig and the 3 rd jig being changeable by moving in the axial direction of the 1 st jig; and a 3 rd step of forming a film on the outer peripheral surface of the annular member in a state where the outer peripheral surface of the sealing member is exposed between the 2 nd jig and the 3 rd jig.
The method for manufacturing an electronic device according to 1 aspect of the present disclosure includes: generating laser light by an excimer laser apparatus including a laser cavity, outputting the laser light to an exposure apparatus, and exposing the laser light on a photosensitive substrate in the exposure apparatus to manufacture an electronic device, wherein the laser cavity has: a container which includes a 1 st member and a 2 nd member and contains laser gas therein; and a sealing member disposed between 2 facing sealing surfaces of the 1 st member and the 2 nd member, wherein a surface of the sealing member on the laser gas side is made of a fluororubber, and a surface of the sealing member on the atmosphere side is made of a film that suppresses atmospheric permeation.
Drawings
Several embodiments of the present disclosure will be described below as simple examples with reference to the drawings.
Fig. 1A schematically shows the structure of an excimer laser apparatus of a comparative example.
Fig. 1B schematically shows the structure of an excimer laser apparatus of a comparative example.
Fig. 2 is a sectional view showing a configuration example of a sealing mechanism using a sealing member in a comparative example.
Fig. 3 is a cross-sectional view enlarged in part of the sealing structure shown in fig. 2.
Fig. 4 is a sectional view showing a part of a seal structure in embodiment 1 of the present disclosure.
Fig. 5 schematically shows a cross section of a seal member in embodiment 2 of the present disclosure.
Fig. 6A schematically shows the structure of an excimer laser apparatus according to embodiment 3 of the present disclosure.
Fig. 6B schematically shows the structure of an excimer laser apparatus according to embodiment 3 of the present disclosure.
Fig. 7A schematically shows a jig set used in the method for manufacturing a seal member according to embodiment 4 of the present disclosure.
Fig. 7B is a sectional view showing an internal configuration of the jig set shown in fig. 7A.
Fig. 7C schematically illustrates a method of manufacturing a seal member according to embodiment 4 of the present disclosure.
Fig. 7D schematically illustrates a method of manufacturing a seal member according to embodiment 4 of the present disclosure.
Fig. 8A schematically illustrates a method of manufacturing a seal member according to embodiment 5 of the present disclosure.
Fig. 8B schematically illustrates a method of manufacturing a seal member according to embodiment 5 of the present disclosure.
Fig. 8C schematically illustrates a method of manufacturing a seal member according to embodiment 5 of the present disclosure.
Fig. 8D schematically illustrates a method of manufacturing a seal member according to embodiment 5 of the present disclosure.
Fig. 9 schematically shows the structure of an exposure apparatus connected to an excimer laser apparatus.
Detailed Description
< content >
1. Comparative example
1.1 Structure of excimer laser device
1.2 action of excimer laser device
1.3 sealing parts
1.3.1 sealing Structure of holder 16a and optical Crystal 16
1.3.2 sealing arrangement of Container part 10b and Window 10f
1.3.3 sealing construction of other Container parts
1.4 problems
2. Sealing member having film for inhibiting atmospheric permeation
2.1 Structure
2.2 action
2.3 others
3. Sealing member having multilayer film
4. Examples of container parts
5. Clamp set
5.1 Structure
5.2 actions
6. Method for forming film having multiple layers
7. Others
Embodiments of the present disclosure will be described in detail below with reference to the drawings. The embodiments described below are merely examples of the present disclosure, and do not limit the present disclosure. Note that the structures and operations described in the embodiments are not necessarily all necessary for the structures and operations of the present disclosure. The same components are denoted by the same reference numerals, and redundant description thereof is omitted.
1. Comparative example
1.1 Structure of excimer laser device
Fig. 1A and 1B schematically show the structure of an excimer laser apparatus of a comparative example. Fig. 1A shows an internal structure of the excimer laser apparatus as viewed from a direction substantially perpendicular to a discharge direction between the pair of discharge electrodes 11A and 11b and substantially perpendicular to a traveling direction of laser light output from the output coupling mirror 15. Fig. 1B shows the internal structure of the excimer laser apparatus as viewed from a direction substantially parallel to the traveling direction of the laser light output from the output coupling mirror 15. The traveling direction of the laser light output from the output coupling mirror 15 is set to the + Z direction. The discharge direction between the discharge electrodes 11a and 11b is set to the + V direction or the-V direction. The direction perpendicular to these two directions is set as the + H direction or the-H direction. the-V direction substantially coincides with the direction of gravity.
As shown in fig. 1A, an excimer laser apparatus is used with the exposure apparatus 100. The laser light output from the excimer laser apparatus is incident on the exposure apparatus 100. The exposure apparatus 100 includes an exposure apparatus control unit 110. The exposure device control unit 110 is configured to control the exposure device 100. The exposure apparatus control unit 110 is configured to transmit setting data of a target pulse energy and a light emission trigger signal to the laser control unit 30 included in the alignment molecule laser apparatus.
The excimer laser apparatus includes a laser cavity 10, a charger 12, a pulse power module 13, a narrowband module 14, an output coupling mirror 15, an energy monitor 17, a cross flow fan 21, a motor 22, a heat exchanger 23, and a laser control section 30. The laser controller 30 performs overall control of the entire molecular laser device.
The laser cavity 10 comprises container parts 10a and 10 b. The laser cavity 10 is disposed on the optical path of a laser resonator including a narrowing-down module 14 and an output coupling mirror 15. There are 2 windows 10f and 10g in the laser cavity 10. The laser cavity 10 houses discharge electrodes 11a and 11 b. The laser cavity 10 accommodates laser gas as a laser medium. The laser gas includes, for example, argon, fluorine gas, and neon gas. Alternatively, the laser gas includes, for example, krypton gas, fluorine gas, and neon gas.
An opening is formed in a part of the container member 10b, and the opening is closed by the electrical insulating portion 20. The electrical insulating portion 20 supports the discharge electrode 11 a. A plurality of conductive portions 20a are embedded in the electrical insulating portion 20. The conductive portions 20a are electrically connected to the discharge electrodes 11a, respectively.
A return plate 10c is disposed inside the laser cavity 10. The container member 10B and the return plate 10c are electrically connected to each other through the wiring portion 10d and the wiring portion 10e shown in fig. 1B. The reflow plate 10c supports the discharge electrode 11 b. The return plate 10c is electrically connected to the discharge electrode 11 b.
As shown in fig. 1B, the reflow plate 10c has gaps for passing the laser gas on the back side and the front side of the sheet of fig. 1A.
The cross flow fan 21 is disposed inside the laser cavity 10. The rotation shaft of the cross flow fan 21 is connected to a motor 22 disposed outside the laser cavity 10. The cross flow fan 21 is rotated by the motor 22. Thereby, the laser gas circulates inside the laser cavity 10 as indicated by the arrow a in fig. 1B. The heat exchanger 23 discharges thermal energy of the laser gas having a high temperature due to the discharge to the outside of the laser cavity 10.
The charger 12 holds electric power for supplying to the pulse power module 13. The pulse power module 13 includes a charging capacitor and a switch 13a, which are not shown. The charger 12 is connected to a charging capacitor of the pulse power module 13. A discharge electrode 11a is connected to the charge capacitor of the pulse power module 13.
The narrowing module 14 includes wavelength selective elements such as a prism 14a and a grating 14 b. Instead of the narrow-banded module 14, a high-reflection mirror may be used.
The output coupling mirror 15 is constituted by a partially reflecting mirror.
The energy monitor 17 includes a beam splitter 17a, a condenser lens 17b, and a photosensor 17 c. The beam splitter 17a is disposed on the optical path of the laser light output from the output coupling mirror 15. The beam splitter 17a is configured to transmit a part of the laser light output from the output coupling mirror 15 through the exposure apparatus 100 with high transmittance and to reflect the other part. The condenser lens 17b and the optical sensor 17c are disposed on the optical path of the laser beam reflected by the beam splitter 17 a.
1.2 action of excimer laser device
The laser control section 30 receives setting data of a target pulse energy and a light emission trigger signal from the exposure device control section 110. The laser control unit 30 transmits the setting data of the charging voltage to the charger 12 based on the setting data of the target pulse energy received from the exposure device control unit 110. The laser control unit 30 also transmits a trigger signal to the pulse power module 13 in response to the light emission trigger signal received from the exposure device control unit 110.
Upon receiving the trigger signal from the laser control unit 30, the pulse power module 13 generates a pulse-like high voltage from the electric energy charged by the charger 12, and applies the high voltage between the discharge electrodes 11a and 11 b.
When a high voltage is applied between the discharge electrodes 11a and 11b, a discharge is caused between the discharge electrodes 11a and 11 b. By the energy of this discharge, the laser gas in the laser cavity 10 is excited and transitions to a high energy level. When the excited laser gas then transitions to a low level, light of a wavelength corresponding to the level difference is emitted.
Light generated in the laser cavity 10 is emitted to the outside of the laser cavity 10 via the windows 10f and 10 g. The light emitted from the window 10f of the laser cavity 10 is expanded in beam width by the prism 14a and enters the grating 14 b. The light incident on the grating 14b from the prism 14a is reflected by the plurality of grooves of the grating 14b, and is diffracted in a direction corresponding to the wavelength of the light. The grating 14b is configured to be littrow so that the incident angle of light incident on the grating 14b from the prism 14a coincides with the diffraction angle of diffracted light of a desired wavelength. Thereby, light near the desired wavelength is returned to the laser cavity 10 via the prism 14 a.
The output coupling mirror 15 transmits a part of the light emitted from the window 10g of the laser cavity 10 to output the light, and reflects the other part of the light to return to the laser cavity 10.
In this way, the light exiting the laser cavity 10 reciprocates between the narrowband module 14 and the output coupling mirror 15. This light is amplified every time it passes through the discharge space between the discharge electrodes 11a and 11 b. The light is narrowed whenever the narrowing module 14 is turned back. The light thus oscillated and narrowed is output as laser light from the output coupling mirror 15.
The condenser lens 17b included in the energy monitor 17 condenses the laser light reflected by the beam splitter 17a on the photosensor 17 c. The optical sensor 17c transmits an electric signal corresponding to the pulse energy of the laser beam condensed by the condenser lens 17b to the laser control unit 30 as measurement data.
The laser control unit 30 receives measurement data from the energy monitor 17. The laser control unit 30 feedback-controls the charging voltage set by the charger 12 based on the measurement data of the pulse energy received from the energy monitor 17 and the setting data of the target pulse energy received from the exposure apparatus control unit 110.
1.3 sealing parts
Fig. 2 is a sectional view showing a configuration example of a sealing mechanism using a sealing member in a comparative example. Fig. 2 shows a case where the container member 10b and the window 10f are sealed, and the holder 16a of the window 10f and the optical crystal 16 are sealed.
1.3.1 sealing Structure of holder 16a and optical Crystal 16
The window 10f includes an optical crystal 16 and holding frames 16a and 16 b. The optical crystal 16 is held between holding frames 16a and 16 b. The holder 16a has an opening 16 h. The holder 16a has a groove 16i around the opening 16 h. The holder 16b has an opening 16 k.
A seal member 16j is disposed between the optical crystal 16 and the holder 16 a. The seal member 16j is disposed in the groove 16 i. The seal member 16j is an annular O-ring. A buffer 16e is disposed between the optical crystal 16 and the holder 16 b.
Around the optical crystal 16, the holder 16a and the holder 16b are fixed to each other by bolts or the like, not shown. The optical crystal 16 is formed of, for example, a crystal of calcium fluoride, and is formed in a disk shape. The holder 16b is made of, for example, ceramic or aluminum. The buffer material 16e is made of, for example, stainless steel or aluminum.
By forming the window 10f as described above, the optical crystal 16 blocks the opening 16h of the holder 16 a. The opening 16h is sealed by a seal member 16j disposed between 2 opposed seal surfaces of the optical crystal 16 and the holder 16a, and the laser gas side and the atmosphere side are blocked.
1.3.2 sealing arrangement of Container part 10b and Window 10f
The container member 10b has an opening 10 h.
The container member 10b has a groove 10i around the opening 10 h. A seal member 10j is disposed in the groove 10 i. The seal member 10j is an annular O-ring. Around the groove 10i and the seal member 10j, the container member 10b and the retainers 16a and 16b of the window 10f are fixed to each other by bolts or the like, not shown. In this example, the container part 10b corresponds to the 1 st part in the present disclosure, and the window 10f corresponds to the 2 nd part in the present disclosure. The container member 10b is made of metal such as nickel-plated aluminum. The holders 16a and 16b of the window 10f are made of, for example, ceramic or aluminum.
With the above configuration, the window 10f closes the opening 10h of the container member 10 b. The opening 10h is sealed by a sealing member 10j disposed between 2 opposing sealing surfaces of the container member 10b and the window 10f, and the laser gas side and the atmosphere side are blocked.
The pulse laser light can pass through the opening 10h of the container member 10b, the opening 16h of the holder 16a, the central portion of the optical crystal 16, and the opening 16k of the holder 16 b.
1.3.3 sealing construction of other Container parts
Referring again to fig. 1A and 1B, the electrical insulating portion 20 is sealed by an annular sealing member 10k disposed around the opening of the container member 10B. Around the sealing member 10k, the container member 10b and the electrical insulating portion 20 are fixed to each other by bolts or the like, not shown. In this case, the container member 10b corresponds to the 1 st member in the present disclosure, and the electrical insulating portion 20 corresponds to the 2 nd member in the present disclosure. The container member 10b is made of metal such as nickel-plated aluminum. The electrical insulating portion 20 is made of, for example, ceramic.
With this configuration, the electrical insulating portion 20 closes the opening of the container member 10 b. The laser gas side and the atmosphere side are blocked by the seal member 10k disposed between the 2 opposed seal surfaces of the container member 10b and the electrical insulating portion 20.
The container member 10b is sealed by an annular seal member 10m disposed around the opening of the container member 10 a. Around the sealing member 10m, the container member 10a and the container member 10b are fixed to each other by bolts or the like, not shown. In this case, the container member 10a corresponds to the 1 st member in the present disclosure, and the container member 10b corresponds to the 2 nd member in the present disclosure. The container members 10a and 10b are made of metal such as nickel-plated aluminum, for example.
With this configuration, the container member 10b closes the opening of the container member 10 a. The laser gas side and the atmosphere side are blocked by the sealing member 10m disposed between the 2 opposing sealing surfaces of the container member 10a and the container member 10 b.
1.4 problems
Fig. 3 is a cross-sectional view enlarged in part of the sealing structure shown in fig. 2. The metal constituting the container member 10b and the ceramic constituting the holder 16a of the window 10f have different thermal expansion coefficients. Therefore, an elastic body is preferably used as the seal member 10 j. By using an elastic body as the seal member 10j, it is possible to absorb the displacement caused by the difference in thermal expansion between the container member 10b and the holder 16a of the window 10 f. As the sealing member 10j, for example, fluororubber having resistance to fluorine gas is preferably used. The fluororubber is preferably a fluoroelastomer or Viton (registered trademark), for example. The sealing member 16j described with reference to fig. 2 is also preferably made of a similar elastic material to suppress damage to the optical crystal 16.
However, the sealing member 10j may not allow the atmospheric air to pass from the atmosphere side to the inside of the laser cavity 10 to become 0. The number of air permeation paths in the seal member 10j is as follows 2. The 1 st permeation pathway is a permeation pathway along the sealing surface of the container member 10b or the holder 16a contacting the seal member 10j, and is indicated by a broken-line arrow in fig. 3. The 2 nd permeation pathway is a permeation pathway passing through the inside of the seal member 10j and is indicated by a solid arrow in fig. 3. When an elastic body is used as the seal member 10j, the 2 nd permeation pathway may allow atmospheric air to permeate therethrough by a factor of 10 or more as compared with the 1 st permeation pathway. For example, oxygen or water vapor in the atmosphere sometimes permeates the elastomer. When the atmosphere passes from the atmosphere side to the inside of the laser cavity 10, the laser gas inside the laser cavity 10 is contaminated. Therefore, the replacement gas consumption amount sometimes increases.
In the embodiments described below, a film that suppresses the permeation of air is formed on the surface of the sealing member on the air side. By using the sealing member having the film, permeation of the atmosphere through the inside of the sealing member 10j is suppressed, and contamination of the laser gas is suppressed.
2. Sealing member having film for inhibiting atmospheric permeation
2.1 Structure
Fig. 4 is a sectional view showing a part of a seal structure in embodiment 1 of the present disclosure. Fig. 4 relates to embodiment 1, and shows a cross section of a portion corresponding to fig. 3. As shown in fig. 4, a film 10n is formed on the surface of the sealing member 10j on the atmosphere side. The film 10n is not formed on the surface of the sealing member 10j on the laser gas side, and the fluororubber is exposed on the surface of the sealing member 10j on the laser gas side. The film 10n is not formed on the surface of the seal member 10j in contact with the seal surfaces of the container member 10b and the holder 16a, and the fluororubber is in contact with the container member 10b and the holder 16a, respectively.
The film 10n contains, for example, fluorineDiamond-like carbon. Alternatively, the film 10n contains Al2O3、SiO2And TiO.
The thickness of the film 10n is preferably 0.1 μm or more and 0.3 μm or less, for example. The film 10n is preferably formed to have a thickness thicker at a position away from the sealing surfaces of the container member 10b and the holder 16a and thinner at a position close to the sealing surfaces of the container member 10b and the holder 16 a.
2.2 action
In embodiment 1, by forming the film 10n that suppresses the permeation of the atmosphere on the surface of the sealing member 10j on the atmosphere side, the amount of the atmosphere that permeates the inside of the sealing member 10j is reduced to about 50% or less as compared with the case where the film 10n is not formed. Even when a crack occurs on the surface of the film 10n, the sealing member 10j is considered to have a small influence on the performance of suppressing the permeation of air because most of the surface on the air side is covered with the film 10 n.
Further, according to embodiment 1, similarly to the comparative example, the amount of atmospheric air passing along the seal surface of the container member 10b or the retainer 16a in contact with the seal member 10j can be small. Further, the fastening force of the holder 16a to the container member 10b can be the same as that in the above comparative example.
Further, when a similar film is formed on the surface of the seal member 10j in contact with the seal surfaces of the container member 10b and the holder 16a, if a crack is generated in the film, the sealing performance may be lost. Therefore, it is preferable that no film be formed on the surface of the seal member 10j that contacts the seal surface of the container member 10b and the holder 16 a.
Further, according to embodiment 1, since the fluororubber is exposed on the surface of the sealing member 10j on the laser gas side, it can have the same resistance to fluorine gas as in the comparative example. Since the film 10n has low resistance against fluorine gas, it is preferable that no film 10n be formed on the surface of the sealing member 10j on the laser gas side.
2.3 others
Fig. 3 shows the sealing member 10j disposed between the container member 10b and the holder 16a of the window 10f, but the present disclosure is not limited thereto.
A film that suppresses the permeation of air may be formed on the surface on the atmosphere side of the sealing member 16j disposed between the optical crystal 16 and the holder 16a shown in fig. 2. A film that suppresses the permeation of air may be formed on the surface of the sealing member 10k on the air side, which is disposed between the container member 10B and the electrical insulating portion 20 shown in fig. 1A and 1B. Further, a film that suppresses the permeation of air may be formed on the surface of the sealing member 10m disposed between the container member 10a and the container member 10B shown in fig. 1A and 1B on the air side.
3. Sealing member having multilayer film
Fig. 5 schematically shows a cross section of a seal member in embodiment 2 of the present disclosure. The film 10n formed on the sealing member 10j includes a plurality of layers that suppress permeation of air.
The plurality of layers includes a 1 st layer L1 and a 2 nd layer L2 located on the atmospheric side of the 1 st layer L1. The plurality of layers is not limited to 2 layers, and may include 3 or more layers. When a plurality of layers are included, the thickness of the film 10n is preferably 0.1 μm or more and 0.3 μm or less.
The area of the 2 nd layer L2 is preferably smaller than the area of the 1 st layer L1. Further, the thickness of the 2 nd layer L2 is preferably smaller than the thickness of the 1 st layer L1. Thus, even if stress is applied to the sealing member 10j, peeling or cracking of the film 10n can be suppressed.
Otherwise, the same as embodiment 1.
4. Examples of container parts
Fig. 6A and 6B schematically illustrate the structure of an excimer laser apparatus according to embodiment 3 of the present disclosure. Fig. 6A and 6B are sectional views of portions corresponding to fig. 1A and 1B, respectively. However, in fig. 6A, illustration of a laser resonator and the like disposed outside the laser cavity 10 is omitted.
In embodiment 3, laser cavity 10 includes container components 10p, 10q, and 10 r. The container member 10p is a cylindrical member. Container members 10q and 10r are disposed at the openings of the + Z direction and-Z direction end portions of container member 10p, respectively.
The container member 10q is sealed by an annular seal member 10s disposed around the opening of the end portion of the container member 10p in the + Z direction. Around the seal member 10s, the container member 10p and the container member 10q are fixed to each other by bolts or the like, not shown. In this case, the container member 10p corresponds to the 1 st member in the present disclosure, and the container member 10q corresponds to the 2 nd member in the present disclosure. The container members 10p and 10q are made of metal such as nickel-plated aluminum, for example.
With this configuration, the container member 10q closes the opening of the container member 10 p. The laser gas side and the atmosphere side are blocked by the sealing member 10s disposed between the 2 opposing sealing surfaces of the container member 10p and the container member 10 q.
A film for suppressing the permeation of air may be formed on the surface of the sealing member 10s on the air side.
Similarly, the container member 10r is sealed by an annular seal member 10t disposed around the opening of the end portion of the container member 10p in the-Z direction. Around the seal member 10t, the container member 10p and the container member 10r are fixed to each other by bolts or the like, not shown. In this case, the container member 10p corresponds to the 1 st member in the present disclosure, and the container member 10r corresponds to the 2 nd member in the present disclosure. The container members 10p and 10r are made of metal such as nickel-plated aluminum, for example.
With this configuration, the container member 10r closes the opening of the container member 10 p. The laser gas side and the atmosphere side are blocked by the seal member 10t disposed between the 2 opposed seal surfaces of the container member 10p and the container member 10 r.
A film for suppressing permeation of air may be formed on the surface of the sealing member 10t on the air side.
Otherwise, the same as in embodiments 1 and 2.
5. Clamp set
5.1 Structure
Fig. 7A schematically shows a jig set used in the method for manufacturing a seal member according to embodiment 4 of the present disclosure. Fig. 7B is a sectional view showing an internal configuration of the jig set shown in fig. 7A.
The jig set includes 1 st to 3 rd jigs 61 to 63. The 1 st jig 61 has a substantially cylindrical shape. The 1 st clamp 61 has male screw portions 61a and 61b at both ends in the axial direction. The 1 st jig 61 has a tapered portion 61c near the center in the axial direction. The tapered portion 61c has the following shape: the diameter is reduced as the 1 st jig 61 approaches the male screw portion 61a in the axial direction.
A cylindrical portion 61d having a diameter slightly larger than the diameters of the male screw portion 61a and the tapered portion 61c is disposed between the male screw portion 61a and the tapered portion 61 c. A cylindrical portion 61e having a diameter slightly larger than the diameters of the male screw portion 61b and the tapered portion 61c is disposed between the male screw portion 61b and the tapered portion 61 c.
The 2 nd jig 62 is a cylindrical member disposed on the outer periphery of the cylindrical portion 61d of the 1 st jig 61. The 2 nd jig 62 is configured to be movable in the axial direction of the 1 st jig 61.
The 3 rd jig 63 is a cylindrical member disposed on the outer periphery of the cylindrical portion 61e of the 1 st jig 61. The 3 rd chuck 63 is configured to be movable in the axial direction of the 1 st chuck 61.
A nut 64 is coupled to the external thread portion 61 a. By rotating the nut 64 around the axis of the 1 st jig 61, the nut 64 moves in the axial direction of the 1 st jig 61. This enables the position of the 2 nd jig 62 to be changed.
A nut 65 is coupled to the external thread portion 61 b. By rotating the nut 65 about the axis of the 1 st jig 61, the nut 65 moves in the axial direction of the 1 st jig 61. This enables the position of the 3 rd jig 63 to be changed.
By changing the position of the 2 nd jig 62 or the position of the 3 rd jig 63, the interval between the 2 nd jig 62 and the 3 rd jig 63 can be changed.
The mechanism for moving the 2 nd jig 62 and the 3 rd jig 63 in the axial direction of the 1 st jig 62 may not use the nuts 64 and 65.
5.2 actions
The following steps are performed using a jig set including the 1 st to 3 rd jigs 61 to 63 to manufacture an annular seal member 10j having a film on a part of the surface thereof.
As a first step, as shown in fig. 7A and 7B, an annular member 10u constituting a seal member 10j is fitted to the outer periphery of the tapered portion 61c of the 1 st jig 61.
As the 2 nd step, as shown in fig. 7C, the annular member 10u is sandwiched between the 2 nd jig 62 and the 3 rd jig 63, and the outer peripheral surface of the annular member 10u is exposed between the 2 nd jig 62 and the 3 rd jig 63.
As the 3 rd step, as shown in fig. 7D, a film 10n is formed on the outer peripheral surface of the annular member 10u in a state where the outer peripheral surface of the annular member 10u is exposed between the 2 nd jig 62 and the 3 rd jig 63.
As shown in fig. 4, the minor axis length of the cross section of the annular member 10u when used as a seal member is a. In the above-described 2 nd step, the interval between the 2 nd jig 62 and the 3 rd jig 63 may be adjusted in a state where the annular member 10u is pressed by the 2 nd jig 62 and the 3 rd jig 63 in the axial direction of the 1 st jig 61. This enables the short axis length a of the cross section of the annular member 10u to be set to a predetermined value.
As shown in fig. 4, the major axis length of the cross section of the annular member 10u when used as a seal member is B, and the contact length of the annular member 10u with the seal surface is d. In the step 1, the inner peripheral surface of the annular member 10u may be brought into contact with the tapered portion 61 c. In the 2 nd step, the position of the annular member 10u in contact with the tapered portion 61c is adjusted by adjusting the position of the 2 nd jig 62 and the position of the 3 rd jig 63, respectively. The inner diameter of the annular member 10u is defined by the contact position of the annular member 10u with the tapered portion 61 c. Thus, the contact length d of the annular member 10u with the seal surface can be adjusted separately from the long axis length B of the cross section of the annular member 10 u.
By forming the film 10n by performing such size adjustment, the film 10n can be formed in conformity with the shape of the sealing member 10j when the sealing member 10j is actually used.
When the diameter of the cross section of the seal member 10j in the state where the uncompressed seal member 10j is provided is L as shown in fig. 7A and 7B, and the width of the groove 10i is D as shown in fig. 4, the following relationship is preferable.
D>L2When the ratio is/A, d is about L2/2A
D≤L2When/. alpha, D is about equal to D/2
6. Method for forming film having multiple layers
Fig. 8A to 8D schematically illustrate a method of manufacturing a seal member according to embodiment 5 of the present disclosure. The jig set used in embodiment 5 is the same as the jig set described with reference to fig. 7A to 7D. In embodiment 5, a film including a plurality of layers is formed by the following method to manufacture a sealing member.
As a 1 st step, the annular member 10u constituting the seal member 10j is fitted to the outer periphery of the tapered portion 61c of the 1 st jig 61. This point is the same as the case described with reference to fig. 7A and 7B.
In the 2 nd step, the annular member 10u is sandwiched between the 2 nd jig 62 and the 3 rd jig 63 so that the outer peripheral surface of the annular member 10u is exposed between the 2 nd jig 62 and the 3 rd jig 63. At this time, as shown in fig. 8A, the position of the 2 nd jig 62 is set to the 1 st predetermined position. The 1 st predetermined position is shown as a distance P1 from the lower end of the male screw portion 61a in fig. 8A. The distance between the 3 rd jig 63 and the 2 nd jig 62 is set to the 1 st predetermined distance D1.
As the 3 rd step, as shown in fig. 8B, the 1 st layer L1 is formed on the outer peripheral surface of the annular member 10u in a state where the outer peripheral surface of the annular member 10u is exposed between the 2 nd jig 62 and the 3 rd jig 63. For forming the 1 st layer L1, a plasma ion implantation film forming method, for example, can be used. For example, as shown in fig. 8B, a jig set having the annular member 10u mounted thereon is housed inside the film forming chamber 50 having the gas introduction passage 51, the power source 52, the plasma electrode 53, and the ground 54. The film forming gas is introduced into the film forming chamber 50 from the gas introduction passage 51, and is converted into plasma by electric energy supplied from the power source 52 to the plasma electrode 53. Ions of the film forming gas are deposited on the outer peripheral surface of the annular member 10u, thereby forming the 1 st layer L1.
The 3 rd step further includes a step of moving the 2 nd jig 62 and the 3 rd jig 63 after the 1 st layer L1 is formed. The 2 nd jig 62 is moved to the 2 nd predetermined position in a direction farther from the 3 rd jig 63 than the 1 st predetermined position. The 2 nd predetermined position is shown as a distance P2 from the lower end of the male screw portion 61a in fig. 8C. The distance between the 3 rd jig 63 and the 2 nd jig 62 is a 2 nd predetermined distance D2 shorter than the 1 st predetermined distance D1. As a result, as shown in fig. 8C, the annular member 10u moves to a position closer to the male screw portion 61a than in the state shown in fig. 8A, that is, to a position where the diameter of the tapered portion 61C is small. Further, the annular member 10u is compressed in the axial direction of the 1 st jig 61, as compared with the state shown in fig. 8A. This increases the contact length d of the annular member 10u with the seal surface.
The 3 rd step further includes the following steps: after moving the 2 nd and 3 rd jigs 62 and 63, as shown in fig. 8D, the 2 nd layer L2 is formed on the surface of the 1 st layer L1 in a state where the 1 st layer L1 is exposed between the 2 nd and 3 rd jigs 62 and 63. The layer 2L 2 is formed by, for example, the same plasma ion implantation film formation method as that described with reference to fig. 8B. As described with reference to fig. 5, the thickness of the 2 nd layer L2 is preferably smaller than the thickness of the 1 st layer L1. As described with reference to fig. 8C, since the contact length d is longer in the formation of the 2 nd layer L2 than in the formation of the 1 st layer L1, the area of the 2 nd layer L2 is smaller than that of the 1 st layer L1.
The plurality of layers is not limited to 2 layers, and 3 or more layers may be formed. The thickness may be smaller as the outer layer is more. The area may be smaller in the outer layer.
By manufacturing the sealing member 10j as described above, even if stress is applied to the sealing member 10j as described with reference to fig. 5, peeling or cracking of the film 10n can be suppressed.
7. Others
Fig. 9 schematically shows the structure of an exposure apparatus 100 connected to the excimer laser apparatus 1. As described above, the excimer laser apparatus 1 generates laser light and outputs it to the exposure apparatus 100.
In fig. 9, an exposure apparatus 100 includes an illumination optical system 41 and a projection optical system 42. The illumination optical system 41 illuminates the reticle pattern of the reticle stage RT with laser light incident from the excimer laser apparatus 1. The projection optical system 42 performs reduction projection of the laser beam transmitted through the mask plate to form an image on a workpiece, not shown, disposed on the workpiece table WT. The workpiece is a photosensitive substrate such as a semiconductor wafer coated with a photoresist. The exposure apparatus 100 synchronously moves the reticle stage RT and the workpiece stage WT in parallel, thereby exposing the laser light reflecting the reticle pattern on the workpiece. By transferring the device pattern on the semiconductor wafer through the exposure process as described above, an electronic device can be manufactured.
The above description is not limiting, but is simply illustrative. Accordingly, it will be apparent to those skilled in the art that modifications can be made to the embodiments of the disclosure without departing from the claims. Furthermore, it is also apparent to those skilled in the art that the embodiments of the present disclosure are used in combination.
Unless explicitly stated otherwise, the terms used throughout the specification and claims should be interpreted as "non-limiting" terms. For example, a term "comprising" or "includes" should be interpreted as "not being limited to the portion described as being included". The term "having" should be interpreted as "not limited to the portion described as having". In addition, the indefinite article "a" should be construed to mean "at least one" or "one or more". In addition, a term "at least one of A, B and C" should be interpreted as "a", "B", "C", "a + B", "a + C", "B + C", or "a + B + C". Further, the term "A", "B" and "C" should be interpreted to include combinations of these components and components other than "A", "B" and "C".
