JP2004241133A - Excimer lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excimer lamp capable of a long life without oxidation of the electrode arranged on the inner tube side and capable of discharging easily the residual gas remaining in the inner space when substituting nitrogen in the lamp house of the irradiation device, and capable of retaining stable optical output. <P>SOLUTION: This lamp is constructed of a discharge container of double cylindrical tube shape in which an outer tube and an inner tube are arranged on the nearly same tube axis, a discharge gas, a first electrode of optical transparency formed on the outer wall of the outer tube, a second electrode formed on the inner side of the inner tube, a power supply line supplying power to the second electrode, a power supply part that contacts the second electrode by elastic force capable of sliding, and a stopper. A ventilation hole for discharging the remaining gas in the inner space is provided in the inner tube, and prevents oxidation of the second electrode. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an excimer lamp that generates excimer molecules by electric discharge and uses light emitted from the excimer molecules, and more particularly, to discharge gas existing in the inner space of an inner tube in an excimer lamp having a double tube structure. To the ventilation holes.
[0002]
[Prior art]
2. Description of the Related Art In recent years, the use of high-energy vacuum ultraviolet light in semiconductor manufacturing processes, cleaning of liquid crystal substrates, and the like has been actively performed. As a technology of a radiator that effectively emits the vacuum ultraviolet light, there is, for example, Japanese Patent Application Laid-Open No. 1-144560 or US Patent No. 9,837,484. The discharge vessel is filled with a gas that generates excimer molecules, and high-frequency high voltage is applied through a dielectric to generate excimer molecules and use light emitted in the dissociation process of the excimer molecules. An excimer lamp as a radiator is described.
[0003]
This excimer lamp has characteristics not found in conventional low-pressure mercury lamps and high-pressure short arc discharge lamps. For example, light having a short wavelength such as 172 nm, 222 nm, or 308 nm can be almost selectively emitted with high efficiency depending on the gas type sealed in the discharge vessel. Further, as the configuration of the excimer lamp, a dielectric may be disposed between at least one electrode and the discharge space, and the degree of freedom in the lamp shape is high, and the excimer lamp is simpler than the high-pressure short arc discharge lamp and the like. Can be manufactured.
[0004]
Here, FIG. 6 shows a structure of a conventional excimer lamp capable of emitting high-output excimer light, which is mainly used in a semiconductor manufacturing process, cleaning of a liquid crystal substrate, and the like. As a structure of the excimer lamp 100, a discharge vessel 103 including an outer tube 101 and an inner tube 102 is provided, and a light-transmissive first electrode 104 made of a metal net or the like is arranged on an outer wall of the outer tube 101. A second electrode 105 made of an aluminum plate or the like is arranged on the inner wall of the inner tube 102. A high-frequency high-voltage is applied from a high-frequency power source 107 to a light-emitting gas 106 such as xenon sealed in the discharge vessel 103 through the first electrode 104 and the second electrode 105 to generate a discharge.
[0005]
In the excimer lamp 100, a pipe-shaped metal tube or a plate-like member is used as the second electrode 105. However, if the degree of adhesion between the second electrode 105 and the inner tube 102 changes, the amount of power supplied to the discharge space varies, and uniform emission of excimer light cannot be obtained. For this reason, Japanese Patent Laid-Open No. Hei 10-241633 discloses a technique for ensuring the close contact between the second electrode 105 and the inner tube 102. In this publication, the second electrode 105 has a notch over the entire length in the tube axis direction, a plurality of planar elastic members are provided inside the second electrode 105, and the second electrode A structure for pressing the electrode 105 against the inner tube 102 is disclosed. In this structure, stress may be repeatedly applied to the power supply line directly connected to the second electrode in accordance with the expansion and contraction of the second electrode disposed inside, and the disconnection may occur.
[0006]
Then, in order to improve this defect, there is, for example, JP-A-2001-307682. This publication discloses a power supply unit slidably in contact with the second electrode as a power supply structure for supplying a high-frequency high voltage to the second electrode. Further, since the power supply unit is made slidable, it is necessary to fix the power supply line so that the power supply unit does not fall off the second electrode even if the power supply line is pulled. Is disclosed. Specifically, a screw portion for fixing the power supply line to the base, a fixing mechanism for tightening and fixing the power supply line is provided, or a position where the power supply line is pulled between the power supply portion and the base. The above description shows that a stopper for preventing sliding is provided.
In addition, if the power supply line itself is to be held as the fixing method, complicated processing of the base is required, so that the power supply line is located between the power supply portion and the base even at a position where the power supply line is pulled. Are often provided with a stopper for preventing sliding. The power supply line is fixed by pressing a stopper provided on the power supply unit against a shaft hole, which is a hole for inserting a power supply line, provided on a base.
[0007]
The conventional configuration is shown schematically in FIG. The structure of the excimer lamp 100 has a discharge vessel 103 composed of an outer tube 101 and an inner tube 102 in the same manner as described above, and a light-transmissive first material made of a metal net or the like is provided on the outer wall of the outer tube 101. An electrode 104 is arranged, and a second electrode 105 made of an aluminum plate or the like is arranged on the inner wall of the inner tube 102. A high-frequency high-voltage is applied from a high-frequency power source 107 to a light-emitting gas 106 such as xenon sealed in the discharge vessel 103 through the first electrode 104 and the second electrode 105 to generate a discharge. Bases 201 are provided at both ends of the excimer lamp, and a shaft hole 206 is provided at the center of one of the bases 201 so that the power supply line 205 does not slide beyond a certain position even when pulled. The stopper portion 204 is connected to the power supply portion 202, and the stopper portion 204 is pressed against and fixed to the base portion 201 so as to close the shaft hole portion 206. The power supply line 205 is taken out through the shaft hole 206. Further, the second electrode 105 is fixed by a plurality of planar elastic members 203.
[0008]
By the way, since the excimer lamp emits ultraviolet light having a short wavelength, an apparatus equipped with the excimer lamp is used after purging with nitrogen or the like to remove absorption by oxygen. FIG. 8 shows an example of an irradiation apparatus equipped with the excimer lamp. FIG. 8A is a schematic view showing an irradiation device in which a plurality of the excimer lamps are arranged in parallel, and FIG. 8B is a schematic cross-sectional view when viewed from the side of FIG. In the irradiation apparatus, a plurality of excimer lamps 100 are arranged in a lamp house 301, and a quartz glass window 304 is provided between the lamp house 301 and the irradiation object 305. The lamp house 301 is provided with a nitrogen inlet 302 and a nitrogen outlet 303, and the inside of the lamp house 301 is purged with nitrogen to reduce excimer light absorption by oxygen. In addition, air existing inside the inner tube of the double-tube excimer lamp is discharged from one end. However, in the method in which the stopper portion 204 is pressed against the end portion of the base portion 201 and fixed, the shaft hole portion 206 is completely closed by the stopper portion 204 when purging with nitrogen. As a result, one end of the excimer lamp is closed without a gap, and the inside of the inner tube 102 cannot be sufficiently replaced with nitrogen. Further, the second electrode 105 disposed on the inner tube 102 side is oxidized by residual oxygen. There was a problem that said.
[0009]
Further, in the excimer lamp 100 having the double cylindrical discharge vessel 103 and having one end closed by the stopper portion 204, the gas stagnating in the internal space of the inner tube 102 emits gas during the operation of the excimer lamp 100. The excimer lamp 100 is overheated, resulting in a problem that the temperature of the entire excimer lamp 100 increases and the light output decreases.
[0010]
[Patent Document 1]
JP-A-1-144560 [Patent Document 2]
US Patent No. 9,837,484 [Patent Document 3]
JP 10-241633 A [Patent Document 4]
JP 2001-307682 A
[Problems to be solved by the invention]
It is an object of the present invention to provide an excimer lamp that has a long life without being oxidized in an electrode arranged on an inner tube side in a double tube excimer lamp. It is still another object of the present invention to provide an excimer lamp capable of easily discharging a residual gas remaining in an inner tube of the excimer lamp when the lamp house of the irradiation apparatus is replaced with nitrogen and maintaining a stable light output.
[0012]
[Means for Solving the Problems]
The excimer lamp of the present invention is a double cylindrical tubular discharge vessel having a substantially cylindrical outer tube and a substantially cylindrical inner tube, wherein the outer tube and the inner tube are disposed substantially on the same tube axis, A discharge gas sealed in the discharge vessel, a light-transmissive first electrode formed on an outer wall of an outer tube of the discharge vessel, and a light-transmitting first electrode formed on an inner wall of an outer wall of the discharge vessel. A second electrode, a power supply line for supplying power to the second electrode, a power supply unit slidably in contact with a tip of the power supply line on the second electrode by its own elasticity, An excimer lamp that utilizes excimer light emission from excimer molecules generated by the discharge of the discharge gas sealed in the discharge vessel, and discharges gas in the inner space of the inner tube. It is characterized by having ventilation holes.
[0013]
Thus, the gas that has accumulated in the inner space of the double cylindrical tubular discharge vessel is heated, so that oxidation of the second electrode by residual oxygen can be reduced, and as a result, the life of the excimer lamp can be extended. There are advantages. In addition, there is an advantage that stable light output can be maintained by suppressing wear of the electrodes. Further, since the temperature of the gas in contact with the second electrode is lowered by the ventilation, there is a cooling effect on the electrode itself, and the point where the inner tube is damaged by expansion and contraction of the electrode and the damage due to the damage are avoided. There is also an advantage that it can be done.
[0014]
In addition, in addition to the above configuration, the excimer lamp of the present invention further includes a stopper auxiliary member sandwiched between a stopper for preventing the ventilation hole from coming off the power supply unit and a base connected to an end of the excimer lamp. It is characterized by being formed by this.
[0015]
Thus, there is an advantage that the gas can be easily ventilated with a simple configuration without stagnation of the gas in the inner space of the discharge vessel, and residual oxygen that oxidizes the second electrode can be easily removed.
[0016]
The ventilation hole is a hole provided on a base portion connected to an end of the excimer lamp.
[0017]
According to such a configuration, it is possible to easily ventilate the gas in the space inside the discharge vessel without stagnation, and it is possible to easily remove residual oxygen that oxidizes the second electrode.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1A is a schematic sectional view of an excimer lamp according to the present invention. The excimer lamp 1 of the present invention has a substantially cylindrical outer tube 2 and a substantially cylindrical inner tube 3, and a first electrode 4 as a light-transmitting electrode is provided on an outer wall of the outer tube 2. A second electrode 5 is provided on the inner surface of the inner tube. The second electrode 5 is provided with a slidable power supply 6, and the power supply 6 and the power supply line 8 are electrically connected. Also, as shown in the conventional example of FIG. 7, between the power supply line 8 and the power supply unit 6 so that the power supply unit 6 does not fall off from the second electrode 5 when the power supply line 8 is pulled. Is provided with a stopper portion 7. In the first embodiment of the present invention, a stopper auxiliary member 11 is sandwiched between a shaft hole 10 of the base 9 provided at both ends of the excimer lamp in the tube axis direction and the stopper 7, and the base 7 It is fixed so as to press against the shaft hole 10 of the portion 9. The vent hole is formed by the stopper auxiliary member 11 being sandwiched between the shaft hole portion 10 and the stopper portion 7. As shown in FIG. 1B, the relationship between the stopper auxiliary member 11 and the shaft hole 10 is such that, for example, near the apex of the triangular stopper auxiliary member 11 with respect to the cylindrical shaft hole 10. It is in contact with 10. Further, the circular portion of the stopper portion 7 contacts the vicinity of the center of each side of the stopper auxiliary member 11. In addition, the relationship between the shaft hole 10 and the stopper 7 is such that the outer diameter of the stopper 7 is smaller than the hole diameter of the shaft hole 10, and the stopper 7 is not provided if the stopper auxiliary member 11 is not provided. The size is small enough to enter the shaft hole 10. Specifically, the narrower portion a of the stopper auxiliary member 11 is arranged to abut on the stopper portion 7, and the wider width portion b of the stopper auxiliary member 11 is arranged to abut on the shaft hole portion 10. . With such a configuration, the ventilation holes 12 (hatched portions in FIG. 1B) are formed so that the gas existing in the inner space of the inner tube 3 of the excimer lamp 1 can be easily moved. Thereby, the gas in the inner tube 3 can be easily replaced, the oxidation of the second electrode 5 by oxygen remaining in the inner tube 3 can be prevented, and the life of the excimer lamp 1 itself can be extended. There is. Further, the gas existing in the inner space of the inner tube 3 is excessively heated by the second electrode 5 and the excimer lamp 1 itself, thereby promoting oxidation of the second electrode 5 and affecting optical characteristics and the like. This is advantageous in that it can be prevented from being given.
[0019]
FIG. 2 illustrates a plurality of embodiments of the stopper auxiliary member 11. FIG. 1A shows a case of a quadrangle shown as an example of a polygon. The shaft hole 10 shown in FIG. 1B is shown by a broken line, and the stopper 7 is shown by a two-dot chain line. Further, the stopper auxiliary member 11 has a portion a having a width smaller than the outer diameter of the stopper portion 7 and a portion b having a width larger than the hole diameter of the shaft hole portion 10. The part b is configured to contact each member. (B) shows an elliptical shape, (c) shows a cross shape, and (d) shows a spring shape. In any case, the stopper auxiliary member 11 has a portion a having a width smaller than the outer diameter of the stopper portion 7, and the stopper portion 7 is supported by the narrow width portion. Further, there is a portion having a width larger than the hole diameter of the shaft hole portion 10, and the stopper auxiliary member 11 is supported by the shaft hole portion 10 at the wide portion b.
[0020]
FIG. 3 shows a second embodiment of the excimer lamp according to the present invention. FIG. 3A is a cross-sectional view of the excimer lamp 1 when the stopper 7 of the excimer lamp 1 also serves as a ventilation hole. The stopper portion 7 shown in FIG. 3B is provided with a hole 31 on a surface that contacts the base portion 9, and the hole 31 also serves as a ventilation hole. In addition, what is shown by the broken line is the shaft hole 10 of the base 9. FIG. 3C shows a case where the shape of the stopper portion 7 is substantially rectangular, and the portion of the base portion 9 that contacts the shaft hole portion 10 does not cover the entire shaft hole portion 10. As a result, a clearance 32 is formed in the shaft hole 10 which also serves as a ventilation hole, so that ventilation is possible.
[0021]
Next, FIG. 4 shows a third embodiment of the excimer lamp according to the present invention. FIG. 4A is a cross-sectional view of the excimer lamp 1, and shows another example in which the stopper portion 7 of the excimer lamp 1 also serves as a ventilation hole as in the case of FIG. The stopper portion 7 shown in FIG. 4B has a cylindrical shape, and a hole 41 is provided in a part thereof, and the hole 41 also serves as a ventilation hole. FIG. 4C shows that the shape of the stopper portion 7 is a coil shape, and the gap between the pitches of the coil portion also serves as a ventilation hole.
[0022]
FIG. 5 shows a fourth embodiment of the excimer lamp according to the present invention. FIG. 5 is a cross-sectional view of the excimer lamp 1 in a case where the base portion 9 also serves as a ventilation hole instead of the stopper portion 7 of the excimer lamp 1. The stopper portion 7 has a conventional structure in which the stopper portion 7 is in contact with the base portion 9. The base portion 9 is provided with a ventilation hole portion 61 so that gas existing in the inner space of the inner pipe 3 can be discharged. I have.
[0023]
【The invention's effect】
According to the excimer lamp of the present invention, the gas retained in the inner space of the double cylindrical tubular discharge vessel is heated by providing ventilation holes in the inner space of the double cylindrical tubular discharge vessel, and the second gas is heated. It is possible to reduce the possibility that the electrode is oxidized by the residual oxygen, and as a result, it is possible to achieve a longer life of the excimer lamp. In addition, there is an advantage that stable light output can be maintained by suppressing wear of the electrodes. Further, since the temperature of the gas in contact with the second electrode is reduced by the ventilation, there is an effect of cooling the electrode itself, and the point where the inner tube is damaged due to expansion and contraction of the electrode, and damage due to the damage is avoided. There is also an advantage that it can be done.
[0024]
In addition, the above configuration is formed by sandwiching a stopper auxiliary member between a stopper for preventing the power supply unit from coming off and a base portion connected to an end of the excimer lamp, so that the configuration is simple. There is the effect that the gas in the space inside the discharge vessel can be easily ventilated without staying therein, and the residual oxygen that oxidizes the second electrode can be easily removed.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing a first embodiment of an excimer lamp according to the present invention. FIG. 2 is a schematic sectional view showing an embodiment of a stopper auxiliary member according to the present invention. FIG. 3 is a second sectional view showing an excimer lamp according to the present invention. FIG. 4 is a schematic cross-sectional view showing a third embodiment of the excimer lamp according to the present invention. FIG. 5 is a schematic cross-sectional view showing a fourth embodiment of the excimer lamp according to the present invention. 6 is a schematic cross-sectional view showing a conventional excimer lamp. [FIG. 7] is a schematic cross-sectional view showing a conventional excimer lamp. [FIG. 8] A schematic view showing a conventional irradiation apparatus equipped with an excimer lamp.
DESCRIPTION OF SYMBOLS 1 Excimer lamp 2 Outer tube 3 Inner tube 4 1st electrode 5 2nd electrode 6 Power supply part 7 Stopper part 8 Power supply line 9 Base part 10 Shaft hole part 11 Stopper auxiliary member 12 Ventilation hole 31 Hole part 32 Gap part 41 Hole Part 51 Hole part 100 Excimer lamp 101 Outer tube 102 Inner tube 103 Discharge vessel 104 First electrode 105 Second electrode 106 Light emitting gas 107 High frequency power supply 201 Base unit 202 Power supply unit 203 Planar elastic member 204 Stopper unit 205 Power supply line 206 Shaft hole 301 Lamp house 302 Nitrogen inlet 303 Nitrogen outlet 304 Quartz glass window 305 Irradiated object

Claims (3)

A double cylindrical discharge vessel having a substantially cylindrical outer tube and a substantially cylindrical inner tube, wherein the outer tube and the inner tube are disposed substantially on the same tube axis, and sealed in the discharge container; A discharge gas, a light-transmissive first electrode formed on an outer wall of an outer tube of the discharge vessel, a second electrode formed on an inner side of an inner tube that is an outer wall of the discharge vessel, A power supply line for supplying power to the second electrode, a power supply unit slidably contacting the tip of the power supply line with the second electrode by its own elasticity, and a stopper for preventing the power supply unit from coming off. An excimer lamp utilizing excimer light emission from excimer molecules generated by the discharge of the discharge gas sealed in the discharge vessel,
An excimer lamp having a ventilation hole for discharging gas in an inner space of the inner tube. 2. The air vent according to claim 1, wherein the vent hole is formed by sandwiching a stopper auxiliary member between a stopper for preventing the power supply portion from coming off and a base portion connected to an end of the excimer lamp. The excimer lamp as described. 2. The excimer lamp according to claim 1, wherein the ventilation hole is a hole provided on a base portion connected to an end of the excimer lamp.

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