Excimer lamp

Abstract

To provide an excimer lamp that can easily suppress contamination during the manufacturing process and offers high workability. [Solution] The excimer lamp comprises an outer tube extending in the direction of the tube axis, an inner tube positioned inside the outer tube and extending in the direction of the tube axis, a discharge tube in which the outer tube and the inner tube are sealed at the ends in the direction of the tube axis, a light-emitting gas sealed in a light-emitting space sandwiched between the outer tube and the inner tube, an outer electrode positioned on the outer wall surface of the outer tube, an inner electrode positioned on the inner wall surface of the inner tube, a base having a shape that is recessed in the direction of the tube axis and having a recessed region into which the end of the discharge tube in the direction of the tube axis is inserted, and an exhaust pipe remainder having a base on the outer wall surface of the outer tube located within the recessed region and protruding in a direction different from the direction of the tube axis, wherein the tip of the exhaust pipe remainder is located on the discharge tube side of the outer wall surface of the base.

Description

Technical Field

[0001] The present invention relates to an excimer lamp.

Background Art

[0002] Conventionally, an excimer lamp that obtains ultraviolet light by excimer emission is known. In an excimer lamp, a luminescent gas that forms excimer molecules by discharge is enclosed in a light-emitting tube made of a dielectric. Then, for example, a high-frequency voltage is applied to a pair of electrodes disposed on the tube wall of the light-emitting tube, and discharge occurs in the light-emitting tube, so that the atoms of the luminescent gas are excited to enter an excimer state. Ultraviolet light is obtained when this atom transitions to the ground state. The applicant has proposed an excimer lamp shown in Patent Document 1 below, for example.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] FIG. 13 is a cross-sectional view schematically showing the configuration of an excimer lamp according to Patent Document 1. As shown in FIG. 13, the excimer lamp 100 includes a light-emitting tube 90, bases 94 attached to both ends in the tube axis direction of the light-emitting tube 90, an inner electrode 95, an outer electrode 97, and a buffer member 99. In FIG. 13, the tube axis direction of the light-emitting tube 90 is taken as the X direction, and an X-Y-Z coordinate system in which a plane orthogonal to the X direction is the Y-Z plane is also shown.

[0005] As shown in Figure 13, the discharge tube 90 includes an outer tube 91 and an inner tube 92, exhibiting a double-tube structure. The discharge tube 90 is made of a dielectric material such as quartz glass and has a sealing portion 93 in which the end positions of the outer tube 91 and inner tube 92 in the X direction are sealed. The internal space of the discharge tube 90 is filled with a luminescent gas containing a noble gas such as Kr or Xe.

[0006] As shown in Figure 13, the inner electrode 95 is positioned on the inner wall surface of the inner tube 92. The outer electrode 97 is positioned on the outer wall surface of the outer tube 91 and forms a mesh structure. The inner electrode 95 and the outer electrode 97 face each other across the discharge tube 90.

[0007] As shown in Figure 13, the buffer member 99 is positioned between the base 94 and the discharge tube 90 to suppress collisions between them.

[0008] Furthermore, as shown in Figure 13, the discharge tube 90 has an exhaust pipe remnant 105 formed in the sealing portion 93. During the manufacture of the excimer lamp 100, an exhaust pipe (not shown) used to exhaust the gas inside the discharge tube 90 is connected to a part of the sealing portion 93. This exhaust pipe is also used to seal the light-emitting gas into the discharge tube 90. The exhaust pipe remnant 105 is the trace left after sealing by heating and melting the exhaust pipe, and it has a shape that protrudes from the sealing portion 93 in the X direction.

[0009] In the manufacturing process of the excimer lamp 100, first, the ends of the outer tube 91 and the inner tube 92 are heated and sealed. Then, after forming a sealing portion 93 that seals the outer tube 91 and the inner tube 92, the exhaust pipe is connected to the sealing portion 93.

[0010] Incidentally, in the manufacturing process of the excimer lamp 100, fine glass particles generated when the outer tube 91 and inner tube 92 are sealed adhere to the inner surface of the discharge tube 90, causing contamination. Therefore, in the manufacturing process of the excimer lamp 100, a cleaning process is performed to remove these glass particles from the discharge tube 90. More specifically, the discharge tube 90 is immersed in a predetermined cleaning solution, the cleaning solution is introduced into the discharge tube 90 from an exhaust pipe (not shown), and then the cleaning solution is washed out of the discharge tube 90. This cleaning process is complicated and involves many steps because it is necessary to remove the contamination from the inner surface of the discharge tube 90 and to remove the cleaning solution from the discharge tube 90.

[0011] The inventors noticed that glass particles adhering to the discharge tube 90 become firmly fixed to the discharge tube after the outer tube 91 and inner tube 92 are sealed and the discharge tube 90 is cooled. After diligent investigation, the inventors found that by pre-installing an exhaust pipe on the outer wall surface of the outer tube before forming the sealing portion, the glass particles adhering to the discharge tube during the formation of the sealing portion can be easily removed. As a result, it is possible to easily manufacture an excimer lamp that suppresses contamination of the discharge tube by glass particles without performing a cleaning process.

[0012] However, when the exhaust pipe is installed on the outer wall surface of the outer tube, the remaining portion of the exhaust pipe protrudes from the outer wall surface of the outer tube in the completed excimer lamp. When the remaining portion of the exhaust pipe protrudes from the outer wall surface of the outer tube, there is a high possibility that an operator may accidentally collide the remaining portion of the exhaust pipe with other components when installing the excimer lamp in a device that uses ultraviolet light to light-clean objects, for example, and this reduces the workability of the excimer lamp.

[0013] The remaining portion of the exhaust pipe, sealed by heating and melting the exhaust pipe, has a more complex wall thickness and surface compared to the discharge tube, making it a weaker area. If the remaining exhaust pipe is damaged, the light-emitting gas sealed in the discharge tube will leak out, making it difficult to light the excimer lamp. In other words, simply providing the remaining exhaust pipe on the outer wall surface of the outer tube would create a problem that reduces the ease of installation of the excimer lamp in an exposure device.

[0014] In view of the above circumstances, the present invention aims to provide an excimer lamp that can easily suppress contamination during the manufacturing process and has high workability. [Means for solving the problem]

[0015] The excimer lamp according to the present invention is A light-emitting tube comprising an outer tube extending in the direction of the tube axis, an inner tube positioned inside the outer tube and extending in the direction of the tube axis, and the outer tube and the inner tube sealed at the ends relating to the direction of the tube axis, A light-emitting gas sealed in the light-emitting space sandwiched between the outer tube and the inner tube, The outer electrode is positioned on the outer wall surface of the outer tube, An inner electrode is positioned on the inner wall surface of the inner tube, A base having a shape that is recessed in the direction of the tube axis, and having a recessed region into which the end of the discharge tube in the direction of the tube axis is inserted, The exhaust pipe comprises a base portion located on the outer wall surface of the outer pipe within the recessed region, and a remaining portion that protrudes in a direction different from the pipe axis direction, The tip of the remaining portion of the exhaust pipe is characterized in that it is located on the side of the discharge tube that is closer to the outer wall surface of the base.

[0016] According to the above configuration, an exhaust pipe used for exhausting gas from inside the discharge tube is provided on the outer wall surface of the outer tube during the manufacturing process. By providing the exhaust pipe on the outer wall surface of the outer tube, it is possible to supply an inert gas such as nitrogen from the exhaust pipe when sealing the ends of the outer tube and the inner tube. This makes it possible to remove glass particles that have adhered to the inside of the discharge tube during the sealing process of the ends of the outer tube and the inner tube.

[0017] As mentioned above, the fine glass particles generated when the outer and inner tubes are sealed adhere firmly to the discharge tube as it cools after the sealing is complete. In other words, at high temperatures, the discharge tube and the glass particles are more easily separated from each other. Therefore, by supplying gas from the exhaust pipe to the discharge tube, which becomes hot when the outer and inner tubes are melted and sealed, it is possible to remove the glass particles before they adhere to the discharge tube. In other words, with the above configuration, since the exhaust pipe is provided on the outer wall surface of the outer tube, contamination of the discharge tube during the manufacturing process can be easily suppressed.

[0018] Furthermore, with the above configuration, the base of the remaining exhaust pipe is located within the recessed area of ​​the base, and the tip of the remaining exhaust pipe is located on the discharge tube side of the outer wall surface of the base. Therefore, since the remaining exhaust pipe does not protrude from the base, installation is easy when attaching the excimer lamp to, for example, an exposure apparatus. In other words, with the above configuration, contamination during the manufacturing process can be easily suppressed without having to perform a cleaning process such as immersing the discharge tube in a cleaning solution, and the workability of the excimer lamp is improved.

[0019] In the excimer lamp described above, The base has a through hole connecting the inner wall surface of the recessed area and the outer wall surface of the base. The remaining portion of the exhaust pipe may be exposed through the through-hole.

[0020] As mentioned above, the remaining portion of the exhaust pipe has a more complex wall thickness and surface compared to the discharge tube, making it a weaker area. In contrast, with the above configuration, the remaining portion of the exhaust pipe is exposed without protruding from the base, thus preventing interference between the remaining portion of the exhaust pipe and other components such as the base. This suppresses malfunctions of the discharge tube that originate from the remaining portion of the exhaust pipe.

[0021] In the excimer lamp described above, The through-hole may be formed in the shape of a notch, and may be in contact with the outer edge of the base located on the central side of the discharge tube with respect to the axial direction of the tube.

[0022] According to the above configuration, when inserting the discharge tube into the base, the alignment between the remaining part of the exhaust tube and the through-hole can be easily performed, which is preferable.

[0023] Further, the above excimer lamp may have a disk member made of a glass material that is located between the outer tube and the inner tube and is joined to the inner tube between the inner electrode and the remaining part of the exhaust tube in the tube axis direction.

[0024] It is known that the bond between Si and O constituting a glass material such as quartz glass is broken by irradiation with ultraviolet light. Therefore, by the ultraviolet light radiated when the excimer lamp is lit, the reaction in which the bond between Si and O is broken proceeds, and distortion occurs in the discharge tube. In particular, this reaction occurs remarkably by ultraviolet light having a wavelength of 200 nm or less.

[0025] On the other hand, it is known that the bond between Si and O broken by irradiation with ultraviolet light recombines by the repair action of OH groups contained in the glass material. Further, such a repair action becomes more remarkable as the temperature of the glass material is higher. This is because the internal atoms are activated due to the high temperature.

[0026] As described above, the remaining part of the exhaust tube has a thicker wall and a more complex surface than the discharge tube, and it can be said that it is easily affected by the distortion caused by the breakage of Si and O. Although details will be described later, according to the above configuration, in the vicinity of the remaining part of the exhaust tube, the repair action by the above OH groups can be made to proceed easily, and the influence of distortion on the remaining part of the exhaust tube can be suppressed.

[0027] The above excimer lamp may further include a second remaining part of the exhaust tube different from the remaining part of the exhaust tube, which is formed in a sealing part that seals the outer tube and the inner tube at an end on the opposite side of the remaining part of the exhaust tube in the tube axis direction.

Advantages of the Invention

[0028] According to the present invention, an excimer lamp is provided that can easily suppress contamination during the manufacturing process and has high workability. [Brief explanation of the drawing]

[0029] [Figure 1A] This is a cross-sectional view showing an example of the configuration of an excimer lamp according to the present invention. [Figure 1B] Figure 1A is a cross-sectional view of BB. [Figure 2] This is an enlarged view showing in detail the configuration near the base in Figure 1A. [Figure 3] This is a diagram showing the discharge tube and base in a disassembled state. [Figure 4] This is a diagram of the excimer lamp as seen from the +Y direction in the state shown in Figure 2. [Figure 5] This is a diagram showing a scene from the manufacturing process of an excimer lamp. [Figure 6] -This is a diagram showing the state in which the sealing portion on the X side has been formed. [Figure 7] This is a diagram showing the state in which the sealing portion on the +X side has been formed. [Figure 8A] This is a cross-sectional view showing another embodiment of the excimer lamp, following Figure 2. [Figure 8B] Figure 8A is a cross-sectional view of the excimer lamp in the YZ region. [Figure 9A] This is a cross-sectional view showing yet another embodiment of an excimer lamp. [Figure 9B] This is a diagram of the excimer lamp shown in Figure 9A, viewed from the Y direction. [Figure 10A] This is a cross-sectional view showing yet another embodiment of the excimer lamp, following Figure 1A. [Figure 10B] Figure 10A shows the excimer lamp as viewed from the +X direction. [Figure 11] This is a diagram showing an alternative configuration of the inner tube. [Figure 12] This is a diagram showing an alternative configuration of the remaining exhaust pipe section. [Figure 13] This is a schematic cross-sectional view showing the configuration of an excimer lamp according to Patent Document 1. [Modes for carrying out the invention]

[0030] Embodiments of the excimer lamp according to the present invention will be described below with reference to the drawings. Note that the following drawings are schematic illustrations, and the dimensional ratios and numbers shown in the drawings do not necessarily correspond to the actual dimensional ratios and numbers.

[0031] [First Embodiment] Figure 1A is a cross-sectional view showing an example of the configuration of an excimer lamp according to the present invention. Figure 1B is a cross-sectional view of BB in Figure 1A. As shown in Figures 1A and 1B, the excimer lamp 1 comprises a discharge tube 3, an inner electrode 5, an outer electrode 7, and bases (9a, 9b) located at both ends of the discharge tube 3 in the axial direction.

[0032] In the following explanation, an XYZ coordinate system is used, where the axis direction of the discharge tube 3 is defined as the X direction, and the plane perpendicular to the X direction is the YZ plane. Using this definition, Figure 1A corresponds to a cross-sectional view of the excimer lamp 1 cut across the XY plane, and Figure 1B corresponds to a cross-sectional view of the excimer lamp 1 cut across the YZ plane.

[0033] In the following descriptions, for example, when expressing direction and distinguishing between positive and negative directions, the signs will be added, such as "+X direction" and "-X direction". When expressing direction without distinguishing between positive and negative directions, it will simply be written as "X direction". In other words, in this specification, when simply written as "X direction", both "+X direction" and "-X direction" are included. The same applies to the Y direction and Z direction.

[0034] As shown in Figures 1A and 1B, the discharge tube 3 has an outer tube 11, an inner tube 12, a sealing portion (13, 14), and the remaining exhaust tube portion (15, 16). As shown in Figure 1B, the discharge tube 3 has a double-tube structure.

[0035] The outer tube 11 and inner tube 12 are cylindrical, as shown in Figure 1B. The inner tube 12 has an outer diameter smaller than the inner diameter of the outer tube 11 and is positioned inside the outer tube 11. The outer tube 11 surrounds the inner tube 12. Typically, the outer tube 11 and inner tube 12 are arranged coaxially.

[0036] For example, the outer diameter of the outer tube 11 is 15mm to 45mm, and the outer diameter of the inner tube 12 is 3mm to 30mm. Also, the length of both in the X direction is 70mm to 3200mm. For example, the outer diameter of the outer tube 11 is 40mm, the outer diameter of the inner tube 12 is 16mm, and the length of both in the X direction is 1200mm. Also, for example, the thickness of the outer tube 11 is 2mm, and the thickness of the inner tube 12 is 1mm. In this case, the radial width of the ring-shaped light-emitting space S1 when viewed in the X direction is 11mm.

[0037] The sealing portion (13, 14) is formed by sealing the outer tube 11 and the inner tube 12 at the end positions on the +X side and -X side. A predetermined light-emitting gas is sealed in the space between the outer tube 11 and the inner tube 12 (hereinafter referred to as the "light-emitting space S1") at a pressure of, for example, 10 kPa to 100 kPa.

[0038] As will be explained in detail later with reference to Figures 5 to 7, during the manufacture of the excimer lamp 1, an exhaust pipe, used for exhausting the gas from the discharge tube 3 and for sealing the discharge tube 3 with luminescent gas, is connected to a portion of the discharge tube 3. The remaining exhaust pipe portions (15, 16) are traces left after the exhaust pipe has been sealed by heating and melting it. The structure of the remaining exhaust pipe portions (15, 16) will be described later.

[0039] Figure 2 is an enlarged view showing in detail the configuration near the base 9a in Figure 1A, and Figure 3 is a diagram showing the discharge tube 3 and base 9a in a disassembled state. Figure 4 is a diagram showing the excimer lamp 1 as viewed from the +Y direction in the state shown in Figure 2.

[0040] As shown in Figures 2 and 3, the base 9a includes an inner wall surface 31, an outer wall surface 32, an inner bottom surface 33, and an outer bottom surface 34, and has a closed-bottom cylindrical shape with an opening on the side opposite to the bottom surfaces (33, 34). That is, the base 9a has a recessed region 20 formed by the inner wall surface 31 and the inner bottom surface 33 that is recessed in the X direction. For example, the base 9a is made of a conductive material such as aluminum, stainless steel, or an aluminum alloy.

[0041] As shown in Figures 2 and 3, the +X side end of the discharge tube 3 is inserted into the base 9a. From the viewpoint of suppressing collision between the sealing portion 13 and the inner wall surface 31 of the base 9a, a buffer member (not shown) that is elastically deformable in the X direction may be placed between the sealing portion 13 and the base 9a in the X direction. For example, a coil spring or a leaf spring can be used as the buffer member.

[0042] Furthermore, as shown in Figures 1B and 4, the base 9a has a through-hole 21 that connects the inner wall surface 31 and the outer wall surface 32 in the Y direction. The remaining exhaust pipe portion 15 can be seen through the through-hole 21 (see Figure 4). In other words, the remaining exhaust pipe portion 15 is exposed through the through-hole 21. In this embodiment, as shown in Figure 4, the through-hole 21 connects with the outer edge E1 of the base 9a and is formed in a notched shape.

[0043] As shown in Figure 2, the remaining exhaust pipe portion 15 has a base portion 15a and a tip portion 15b. As shown in Figure 2, the base portion 15a is located on the outer wall surface of the outer pipe 11 and within the recessed region 20 of the base 9a. The remaining exhaust pipe portion 15 protrudes from the base portion 15a in a direction different from the X direction. In this embodiment, the remaining exhaust pipe portion 15 protrudes in the Y direction.

[0044] As shown in Figure 2, the tip 15b of the remaining exhaust pipe portion 15 is located on the discharge tube 3 side of the outer wall surface 32 of the base 9a. As mentioned above, the remaining exhaust pipe portion 15 is sealed by heating and melting the exhaust pipe, so its thickness and surface are more complex than those of the discharge tube 3, and it is weaker in strength. Therefore, it is preferable that the tip 15b of the remaining exhaust pipe portion 15 is located on the discharge tube 3 side of the outer wall surface 32 of the base 9a and does not protrude from the outer wall surface 32. This makes it less likely for the remaining exhaust pipe portion 15 to collide with other components when attaching the excimer lamp 1 to an exposure apparatus, for example, and improves the workability of the excimer lamp 1.

[0045] As shown in Figures 1A and 2, an elastic member 25 is arranged on the inner wall surface 31 of the base 9a, which is elastically deformable in the radial direction of the light-emitting tube 3. This elastic member makes it possible to clamp the light-emitting tube 3 inserted into the base 9a. For example, a coil spring or a leaf spring can be used as the elastic member 25. Note that the elastic member 25 is not shown in Figures 1B and 3.

[0046] Since the exhaust pipe remainder 15 is weaker in strength than the light-emitting tube 3, it is preferable that the light-emitting tube 3 is held in place with the elastic member 25 in contact with a portion different from the exhaust pipe remainder 15. Here, as shown in Figure 4, the exhaust pipe remainder 15 is exposed through the through hole 21. Therefore, simply by placing the exhaust pipe remainder 15 inside the through hole 21, the elastic member 25 can be easily brought into contact with a portion different from the exhaust pipe remainder 15, which is preferable.

[0047] Furthermore, as shown in Figure 4, the through-hole 21 is formed in a notched shape, which makes it easy to align the remaining exhaust pipe portion 15 with the through-hole 21 when inserting the discharge tube 3 into the base 9a. In this embodiment, the tip portion 15b of the remaining exhaust pipe portion 15 is located radially outward from the inner wall surface 31 of the base 9a, but this point is arbitrary.

[0048] The same discussion as with base 9a applies to the fact that base 9b has a recessed region that is recessed in the X direction. That is, as shown in Figure 1A, base 9b has a recessed region that is recessed in the -X direction, into which the -X side end of the discharge tube 3 is inserted.

[0049] As shown in Figure 1A, the exhaust pipe remainder 16 is formed in the sealing portion 14 located on the -X side. That is, the base of the exhaust pipe remainder 16 is located in the sealing portion 14, and the exhaust pipe remainder 16 protrudes in the -X direction. As shown in Figure 1A, the exhaust pipe remainder 16 is located within the recessed area of ​​the base 9b. In this embodiment, the exhaust pipe remainder 16 corresponds to the "second exhaust pipe remainder".

[0050] As described with reference to base 9a, base 9b may have an elastic member 25 on its inner wall surface (see Figure 1A). Furthermore, from the viewpoint of suppressing collision between the remaining exhaust pipe portion 16 and the inner bottom surface of base 9b, a buffer member (not shown) may be placed between the sealing portion 14 and base 9b.

[0051] As shown in Figure 1A, the inner electrode 5 is positioned on the inner wall surface of the inner tube 12 and, for example, takes the form of a film. The inner electrode 5 is made of a conductive material such as aluminum, titanium, or stainless steel. The inner electrode 5 may also be made of a plate-shaped member made of a conductive material.

[0052] As shown in Figures 1A and 1B, the outer electrode 7 is arranged on the outer wall surface of the outer tube 11. The outer electrode 7 is made of a conductive material such as stainless steel, nickel, or copper. In this embodiment, the outer electrode 7 has a mesh-like structure, but the shape of the outer electrode 7 is not limited in the present invention. For example, the outer electrode 7 may have a striped structure.

[0053] The outer electrode 7 is, for example, cylindrical when viewed in the X direction, and is positioned on the outer wall surface of the outer tube 11 when the discharge tube 3 is inserted in the X direction. Methods for forming the outer electrode 7 include attaching a mesh of metal wires, applying conductive tape to the outer wall surface, or applying conductive paste to the outer wall surface by screen printing and then firing.

[0054] The inner electrode 5 and the outer electrode 7 face each other, separated by a light-emitting space S1.

[0055] Power supplies (not shown) are connected to the inner electrode 5 and the outer electrode 7, respectively. When a high-frequency AC voltage, for example, of about 10kHz to 100kHz, is applied from the power supply between the inner electrode 5 and the outer electrode 7, ultraviolet light is generated in the light-emitting space S1. This ultraviolet light is extracted from the excimer lamp 1 through the mesh-like gaps in the outer electrode 7. As an example, the input power is set to 20W to 2000W, and the input voltage is set to about 5kV to 15kV.

[0056] Next, the manufacturing process of the excimer lamp 1 will be described. Figure 5 is a diagram showing one scene of the manufacturing process of the excimer lamp 1. As shown in Figure 5, the outer tube 11 and the inner tube 12 are prepared, and the inner tube 12 is placed inside the outer tube 11. The exhaust pipe 40 is connected to the outer wall surface 11a of the outer tube 11. The outer tube 11, the inner tube 12, and the exhaust pipe 40 are made of, for example, quartz glass.

[0057] As an example, first, the ends of the outer tube 11 and the inner tube 12 on the -X side are heated and melted to seal them. In other words, a sealing portion 14 is formed at the end of the discharge tube 3 on the -X side. Figure 6 is a diagram showing the state in which the sealing portion 14 on the -X side has been formed. When forming the sealing portion 14, an inert gas G1 such as nitrogen is introduced into the space between the outer tube 11 and the inner tube 12 from the opening A1 on the +X side. In Figure 6, the inert gas G1 is schematically illustrated. As shown in Figure 6, the inert gas G1 is introduced into the discharge tube 3 from the opening A1 and discharged from the exhaust pipe 40.

[0058] The opening A1 is ring-shaped when viewed in the X direction (see also Figure 1B). When introducing the inert gas G1 through the opening A1, an attachment (not shown) having a gas inlet may be attached to the opening A1.

[0059] When the outer tube 11 and inner tube 12 are sealed, fine glass particles adhere to the inner wall of the discharge tube 3. It is thought that these glass particles adhere more firmly to the inner wall of the discharge tube 3 as the temperature of both the outer tube 11 and inner tube 12 decreases after sealing. In contrast, by passing an inert gas G1 through the discharge tube 3 while the outer tube 11 and inner tube 12 are heated to a high temperature for sealing, the amount of glass particles adhering to the inside of the discharge tube 3 can be reduced. For example, it is possible to maintain the high temperature state of the outer tube 11 and inner tube 12 using any heater.

[0060] Then, after the exhaust pipe 41 is connected to the sealing portion 14 (see Figure 7, described later), the ends of the outer pipe 11 and inner pipe 12 in the +X direction are heated and melted to seal them (sealing portion 13). Figure 7 is a diagram showing the state in which the sealing portion 13 on the +X side has been formed. When forming the sealing portion 13, an inert gas G1 such as nitrogen is introduced from the exhaust pipe 41 into the space between the outer pipe 11 and the inner pipe 12. In Figure 7, the inert gas G1 is schematically illustrated, similar to Figure 6. As shown in Figure 7, the inert gas G1 is introduced into the discharge tube 3 from the exhaust pipe 41 and discharged from the exhaust pipe 40.

[0061] Even when the sealing portion 13 is formed, fine glass particles adhere to the inner wall of the discharge tube 3. However, when the outer tube 11 and inner tube 12 are heated to a high temperature for sealing, and inert gas G1 is passed through the discharge tube 3 (see Figure 7), the amount of glass particles adhering to the inside of the discharge tube 3 can be reduced.

[0062] Then, after the gas in the discharge tube 3 is exhausted via exhaust pipes 40 and 41, a predetermined luminescent gas is sealed inside the discharge tube 3. The wavelength of the ultraviolet light emitted by the excimer lamp 1 is determined by the type of luminescent gas. For example, if a luminescent gas containing Xe is sealed inside the emission space S1, ultraviolet light with a peak wavelength around 172 nm is obtained. However, the present invention is not limited to the type of luminescent gas sealed inside the emission space S1. For example, the excimer lamp 1 may contain Kr and Cl2 as the luminescent gas, with a peak wavelength around 222 nm.

[0063] After the luminescent gas is sealed, the exhaust pipes 40 and 41 are sealed by heating, forming the remaining exhaust pipe portions 15 and 16. Then, after the inner electrode 5 and outer electrode 7 are positioned, bases (9a, 9b) are attached to both ends of the luminescent tube 3 in the X direction.

[0064] If the exhaust pipe 40 is not provided on the outer wall surface 11a of the outer tube 11, in the above example, it would be difficult to form the sealing portion 13 and simultaneously pass the inert gas G1 into the discharge tube 3. Specifically, when forming the sealing portion 14, if an attachment (not shown) having, for example, a gas inlet and a gas exhaust port is attached to the opening A1, it is thought that the inert gas G1 can be passed into the discharge tube 3 when forming the sealing portion 14. However, at the stage of forming the sealing portion 13, only the exhaust pipe 41 provided in the sealing portion 14 is connected to the discharge tube 3, and the inert gas G1 cannot be passed into the discharge tube 3. Furthermore, for this reason, it is not practical to form multiple exhaust pipes 41 in the sealing portion 14.

[0065] In other words, by providing an exhaust pipe 40 on the outer wall surface 11a of the outer tube 11, dirt on the discharge tube 3 during the manufacturing process can be easily removed. More specifically, by allowing inert gas G1 to be passed through the discharge tube 3 when forming the sealing parts 13 and 14, the amount of glass particles adhering to the discharge tube 3 can be reduced. Therefore, an excimer lamp 1 can be obtained with reduced dirt on the discharge tube 3 during the manufacturing process without having to perform a cleaning process that involves immersing the entire discharge tube 3 in a cleaning solution.

[0066] As a result of the above manufacturing process, in the excimer lamp 1, the remaining exhaust pipe portion 15 is located on the outer wall surface of the outer pipe 11 (see Figure 1A, etc.). Furthermore, as mentioned above, the remaining exhaust pipe portion 15 is located within the recessed area 20 of the base 9a and does not protrude from the outer wall surface 32 of the base 9a. This makes the excimer lamp 1 easy to handle when installing it in an exposure device, etc., and improves work efficiency.

[0067] [Alternative Embodiment] The following describes another embodiment of the excimer lamp 1, focusing on the differences from the first embodiment.

[0068] <1> Figures 8A and 8B are cross-sectional views showing another embodiment of the excimer lamp 1, following Figures 2 and 1B. As shown in Figures 8A and 8B, the base 9a has a groove 22 on its inner wall surface 31 that extends in the +X direction from the -X side end, and the remaining exhaust pipe portion 15 may be placed within the groove 22. In other words, the present invention is not limited to a configuration in which the base 9a has a through hole 21 and the remaining exhaust pipe portion 15 is exposed through the through hole 21.

[0069] Furthermore, Figure 9A is a cross-sectional view showing yet another embodiment of the excimer lamp 1, and Figure 9B is a view of the excimer lamp 1 according to Figure 9A from the Y direction. As shown in Figure 9A, the base 9a may have a through hole 23 connecting the groove 22 and the outer wall surface 32 in the Y direction, as in the example of Figure 8A. In this case, as shown in Figure 9B, the through hole 23 is, for example, circular in shape. The through hole 23 may also be rectangular in shape. In other words, in the present invention, the shape of the through holes (21, 23) in the base 9a is not limited to a notched shape.

[0070] <2> Figure 10A is a cross-sectional view showing yet another embodiment of the excimer lamp 1, following Figure 1A. Figure 10B is a view of the excimer lamp 1 according to Figure 10A from the +X direction. In Figure 10B, the base 9a is not shown.

[0071] As shown in Figure 10A, the excimer lamp 1 may have a disc member 45 located between the inner electrode 5 and the remaining exhaust pipe portion 15 with respect to the X direction.

[0072] As shown in Figure 10B, the disc member 45 has an annular shape that extends radially from the inner pipe 12. The disc member 45 is formed from the same material as the inner pipe 12 and is joined to the outer wall surface of the inner pipe 12 by welding. More specifically, the disc member 45 is made of a glass material such as quartz glass. The outer diameter of the disc member 45 is smaller than the inner diameter of the outer pipe 11, and as shown in Figures 10A and 10B, there is a gap between the disc member 45 and the outer pipe 11.

[0073] It is known that irradiation with ultraviolet light breaks the Si-O bond that makes up glass materials such as quartz glass. Therefore, when the excimer lamp 1 is lit, the ultraviolet light emitted from the light-emitting space S1 causes a reaction in which the Si-O bond is broken, resulting in strain in the discharge tube 3. In particular, this reaction occurs significantly with ultraviolet light with a wavelength of 200 nm or less.

[0074] In contrast, it is known that the Si-O bond broken by ultraviolet light irradiation can be recombined by the repair action of OH groups contained in the glass material. Furthermore, this repair action becomes more pronounced as the temperature of the glass material increases. This is because the internal atoms are activated at higher temperatures. In other words, the higher the temperature of the discharge tube 3, the more pronounced the repair action by OH groups becomes, and the strain caused by the breaking of Si and O is relieved.

[0075] Here, as mentioned above, the remaining exhaust pipe portion 15 has a more complex wall thickness and surface compared to the discharge tube 3, and is therefore more susceptible to strain caused by the cutting of Si and O. For this reason, it is preferable to facilitate the repair action by the OH groups in the vicinity of the remaining exhaust pipe portion 15.

[0076] When the excimer lamp 1 is lit, the disc member 45 becomes hot, similar to the discharge tube 3. Therefore, as shown in Figure 10A, by positioning the disc member 45 between the inner electrode 5 and the remaining exhaust pipe portion 15, it is possible to prolong the high-temperature state in the area where the disc member 45 is located after the excimer lamp 1 is turned off. In other words, by providing the disc member 45 on the -X side of the remaining exhaust pipe portion 15, the high-temperature state of the remaining exhaust pipe portion 15 after the excimer lamp 1 is turned off is more likely to persist compared to the case where the disc member 45 is not provided. This suppresses the effect of strain on the remaining exhaust pipe portion 15.

[0077] From the viewpoint of making it easier to maintain a high temperature in the remaining exhaust pipe portion 15, it is preferable that the distance d1 between the remaining exhaust pipe portion 15 and the disc member 45 be small. For example, the distance d1 is preferably 30 mm or less, and particularly preferably 10 mm or less. Note that the distance d1 may be the distance between the outermost radially located portion of the remaining exhaust pipe portion 15 and the disc member 45 in the X direction (see Figure 10A).

[0078] Although not shown in the illustration, in the manufacturing process of the excimer lamp 1, when the inner tube 12 is placed inside the outer tube 11 (see Figure 5), the excimer lamp 1 shown in Figure 10A can be realized by joining a disc member 45 to the outer wall surface of the inner tube 12.

[0079] Figure 11 is a diagram showing another example of the inner tube 12 configuration. The thicker the tube wall region, the easier it is to maintain the high temperature state of the excimer lamp 1 after it is turned off. In view of this, as shown in Figure 11, the inner tube 12 has a region 12a where the tube wall is thicker and a region 12b where the tube wall is thinner than region 12a, and the disc member 45 may be formed in region 12a. This configuration is also preferable in that it makes it easier to join the disc member 45 to the inner tube 12. As an example, the thickness of region 12a is 1 mm to 4 mm, preferably 1.5 mm to 3 mm. The thickness of region 12b is 0.5 mm to 2 mm, preferably 0.8 mm to 1.5 mm.

[0080] <3> The shape of the exhaust pipe remainder (15,16) is not limited to the above. Figure 12 is a diagram showing another example of the exhaust pipe remainder (15,16). As shown in Figure 12, for example, the exhaust pipe remainder 15 may be sealed at a position closer to the discharge tube 3 than the tip portion 15b. Also, as shown in Figure 12, the outer electrode 7 may be positioned extending over the exhaust pipe remainder 15.

[0081] <4> Both the remaining exhaust pipe portion 15 and the remaining exhaust pipe portion 16 may be provided on the outer wall surface of the outer pipe 11. In this case, during the manufacturing process of the excimer lamp 1, the two exhaust pipes are connected to the outer wall surface of the outer pipe 11. As a result, the same discussion as described in the first embodiment is possible regarding the fact that the inert gas G1 can be passed through the discharge tube 3 when forming the sealing portion 13 and the sealing portion 14.

[0082] <5> In the above description, the outer electrode 7 was described as having a mesh-like structure, but the present invention is not limited thereto. For example, the outer electrode 7 may be composed of a wire member wound spirally on the outer wall surface of the outer tube 11 and may have a striped structure.

[0083] <6> The configuration of the excimer lamp 1 according to the present invention is not limited to the illustrated configuration. [Explanation of Symbols]

[0084] 1: Excimer lamp 3: Discharge tube 5: Inner electrode 7: Outer electrode 9a, 9b: Bass 11: Outer tube 12: Inner tube 13,14: Sealing section 15,16: Remaining part of the exhaust pipe 20: Recessed area 21,23: Through hole 22: Groove 25: Elastic member 31: Interior wall surface 32: Exterior wall surface 33: Inner bottom surface 34: Outer bottom surface 40,41: Exhaust pipe 45: Disc member 90: Discharge tube 91 : Outer tube 92: Inner tube 93: Sealing part 94: Bass 95 : Inner electrode 97: Outer electrode 99: Cushioning material 100: Excimer Lamp 105: Remaining part of the exhaust pipe

Claims

1. A light-emitting tube comprising an outer tube extending in the direction of the tube axis, an inner tube positioned inside the outer tube and extending in the direction of the tube axis, and the outer tube and the inner tube sealed at the ends relating to the direction of the tube axis, A light-emitting gas sealed in the light-emitting space sandwiched between the outer tube and the inner tube, The outer electrode is positioned on the outer wall surface of the outer tube, An inner electrode is positioned on the inner wall surface of the inner tube, A base having a shape that is recessed in the direction of the tube axis, and having a recessed region into which the end of the discharge tube in the direction of the tube axis is inserted, The exhaust pipe comprises a base portion located on the outer wall surface of the outer pipe within the recessed region, and a remaining portion that protrudes in a direction different from the pipe axis direction, An excimer lamp characterized in that the tip of the remaining exhaust pipe is located on the side of the discharge tube that is closer to the outer wall surface of the base.

2. The base has a through hole connecting the inner wall surface of the recessed area and the outer wall surface of the base. The excimer lamp according to claim 1, characterized in that the remaining portion of the exhaust pipe is exposed through the through-hole.

3. The excimer lamp according to claim 2, characterized in that the through hole is in contact with the outer edge of the base located on the central side of the discharge tube with respect to the axial direction of the tube, and is formed in the shape of a notch.

4. An excimer lamp according to any one of claims 1 to 3, characterized in that it has a disc member made of glass material located between the outer tube and the inner tube, and joined to the inner tube between the inner electrode and the remaining part of the exhaust pipe in the axial direction of the tube.

5. The excimer lamp according to any one of claims 1 to 3, further comprising a second exhaust pipe portion, separate from the exhaust pipe portion, formed in a sealing portion that seals the outer pipe and the inner pipe at the end opposite to the exhaust pipe portion with respect to the pipe axis.

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