JP2002298790A - Excimer lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase an irradiating amount to an irradiated body while preventing reduction of an excimer light with a simple structure. SOLUTION: A nitride gas 3 is introduced and a reflecting body 4 is provided in a space S between an excimer UV lamp 1 and a protecting tube 2. Thus, an excimer light E1 emitted from an opposite surface side of the excimer UV lamp 1 is directly irradiated to the irradiated body A through the protecting tube 2 without being absorbed. An excimer light E2 emitted to a back surface side other than that is reflected by the reflecting body 4 and is irradiated to the irradiated body A through the protecting tube 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excimer illuminator used for dry cleaning for oxidizing and removing organic contamination adhering to a substrate of a liquid crystal display, quartz glass for a mask or a silicon semiconductor wafer, for example. More specifically, the present invention relates to an excimer illuminating device provided with a reflector that is supplied with nitrogen gas to replace air existing around an excimer UV lamp and reflects excimer light emitted from the excimer UV lamp toward an irradiation target.

[0002]

2. Description of the Related Art Conventionally, as this type of excimer illuminating device, for example, Japanese Patent Laid-Open No.
As disclosed in JP-A-124540, an excimer UV lamp (derivative barrier discharge lamp) is mounted in a container (housing) having a flat irradiation window made of synthetic quartz. Excimer light (vacuum ultraviolet light) emitted from the excimer UV lamp is absorbed through the flat irradiation window without being absorbed,
Irradiation is performed on an object to be irradiated in an oxygen atmosphere, and as a result, bonds of organic substances which are dirt are cut off, and absorbed by oxygen to form ozone and active oxygen. Some are evaporated with nitrogen. In addition, a reflector is arranged in the container so as to surround the excimer UV lamp, and the excimer light reflected by the reflector is radiated to the irradiated object through a flat irradiation window, and the reflector is replaced with nitrogen. Is combined,
The irradiation intensity and irradiation area are improved.

[0003]

However, in such a conventional excimer lighting device, the container and the synthetic quartz flat irradiation window have a sufficient strength against the internal pressure of the nitrogen gas flowing into the container. This necessitates the use of thick-walled containers and thick flat irradiation windows, which increases the manufacturing cost and is not economical.
There is a problem that the object to be irradiated cannot be approached to the lamp, the irradiation efficiency of the excimer light is reduced, and the cleaning efficiency is reduced. Moreover, when it is necessary to arrange a plurality of excimer UV lamps in parallel, the excimer UV lamps are arranged with the thick wall of the container interposed therebetween, so that the electrodes of these excimer UV lamps can be arranged close to each other. However, since the distance between the electrodes is greatly increased, there is a problem that the irradiation efficiency of the irradiation target decreases and the illuminance distribution on the irradiation target easily varies.

An object of the present invention is to increase the amount of irradiation on an irradiation object while preventing attenuation of excimer light with a simple structure. The invention according to claim 2 provides, in addition to the object of the invention according to claim 1, an excimer UV lamp, an object to be irradiated, and a plurality of excimer U.
The purpose is to bring the V lamps closer to each other. The third aspect of the present invention has an object to improve the irradiation intensity and the irradiation area of the irradiation target in addition to the object of the first or second aspect of the present invention.

[0005]

In order to achieve the above-mentioned object, according to the first aspect of the present invention, the excimer UV lamp is formed in a cylindrical shape around a periphery of an excimer UV lamp using a material having excellent excimer light transmittance. A protective tube is provided and these excimer UV
A nitrogen gas is allowed to flow into a space defined between the lamp and the protection tube, and a reflector is provided so that excimer light emitted to the back side of the excimer UV lamp is reflected to the irradiated object. It is a feature. The invention according to a second aspect is characterized in that a configuration in which the protective tube is formed in a cylindrical shape is added to the configuration of the first aspect. Claim 3
The invention described in Claim 1 or 2
The reflecting surface of the reflector is concavely curved along the outer peripheral surface of the excimer UV lamp, and the curvature of the reflecting surface is adjusted so that most of the excimer light emitted from the back side of the excimer UV lamp facing the excimer UV lamp is turned off. It is characterized by adding a configuration that expands outward.

[0006]

According to the first aspect of the present invention, the excimer light emitted from the opposing surface of the excimer UV lamp is absorbed by flowing a nitrogen gas and arranging a reflector in the space between the excimer UV lamp and the protective tube. The excimer light emitted directly to the illuminated object through the protective tube is not reflected, and the excimer light emitted to the other back side is reflected by the reflector and is irradiated to the illuminated object through the protective tube. Things. According to the second aspect of the present invention, since a configuration in which the protective tube is formed in a cylindrical shape is added to the configuration of the first aspect, the cylindrical protective tube is structurally excellent in strength. Even if thin, it can withstand nitrogen gas pressure sufficiently. According to a third aspect of the present invention, in the configuration of the first or second aspect, the reflecting surface of the reflector is curved concavely along the outer peripheral surface of the excimer UV lamp, and the curvature of the reflecting surface is opposed to the curved surface. Most of the excimer light emitted from the back side of the excimer UV lamp
With the addition of a configuration that expands to the outside of the lamp, most of the excimer light emitted from the back side of the excimer UV lamp is reflected by the reflecting surface of the reflector and is not returned to the excimer UV lamp. Irradiated directly onto the illuminated body.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, as shown in FIGS. 1 and 2, an excimer UV lamp 1 is configured such that a reticulated cylindrical internal electrode 1a and a reticulated cylindrical external electrode 1b disposed outside thereof are coaxial. By placing
It has a double-cylindrical structure in which 2 nm excimer light is radiated radially, and shows a case where an irradiation target A is arranged at a predetermined interval from the excimer UV lamp 1.

As shown in FIG. 2, the excimer UV lamp 1 has a holder 1c for supporting the internal electrode 1a and the external electrode 1b at one or both ends in the axial direction, as shown in FIG.
A connection cord (not shown) for applying a high-frequency voltage to the internal electrode 1a and the external electrode 1b is inserted through the holder 1c.

A protection tube 2 for protecting the external electrode 1b is provided on the outer periphery of the excimer UV lamp 1, and a space S is provided between the excimer UV lamp 1 and the protection tube 2.
Is formed.

The protective tube 2 is formed in a cylindrical shape from a material such as synthetic quartz glass having excellent excimer light transmittance, and is disposed coaxially with the internal electrode 1a and the external electrode 1b of the excimer UV lamp 1. .

In the case of this embodiment, the protective tube 2 is formed in a cylindrical shape with both ends or only one end opened, and the opening end 2a is tightly fixed to the holder 1c of the excimer UV lamp 1 to be hermetically closed. A space S is formed.

A nitrogen gas 3 flows into the space S between the excimer UV lamp 1 and the protective tube 2 and light is emitted to the back side of the excimer UV lamp 1 opposite to the surface facing the irradiation object A. The reflector 4 is provided so that the excimer light E2 thus reflected is reflected to the irradiation target A.

The nitrogen gas 3 is supplied to eliminate air existing in the space S, thereby eliminating absorption of excimer light and preventing light energy from being attenuated. The oxidation of the electrode 1b is prevented.

In the case of the present embodiment, an inlet 3a for nitrogen gas 3 is opened at the center of the holder 1c of the excimer UV lamp 1, and nitrogen gas 3 is introduced into the internal electrode 1a from the inlet 3a. The internal electrode 1a and the external electrode 1b are cooled by flowing the air to the tip of the internal electrode 1a and flowing to the space between the internal electrode 1a and the external electrode 1b. Through protection tube 2
The nitrogen gas 3 which has flowed into the space S is discharged to the outside from an outlet 3b opened in the outer peripheral portion of the holder 1c.

The reflecting plate 4 is formed of a material having a high excimer light reflectance, for example, a material such as a metal. In this embodiment, the reflecting surface 4a facing the back side of the excimer UV lamp 1 is connected to an external electrode. The reflecting surface 4a is curved in a concave shape along the outer peripheral surface of the excimer UV lamp 1 so that most of the excimer light emitted from the back side of the excimer UV lamp 1 facing the reflecting surface 4a spreads out of the excimer UV lamp 1. In this case, the curvature of the protection tube 2 is substantially equal to or smaller than the curvature.

In the illustrated example, the reflecting plate 4 is an aluminum plate, and at least the reflecting surface 4a is mirror-finished.
The excimer UV lamp 1 is suspended and fixed to the holder 1c of the excimer UV lamp 1 via a hanger 4b so as not to move.

The excimer illuminating device having the above-described structure is not only provided with one excimer UV lamp 1 for the irradiation object A as shown in FIGS.
As shown in FIG. 3, a plurality of excimer UV lamps 1 may be arranged in parallel according to the size of the irradiation object A.

Next, the operation of the excimer lighting device will be described. First, as shown in FIG. 2, when a high-frequency voltage is applied to the internal electrode 1 a and the external electrode 1 b of the excimer UV lamp 1 in a state where the nitrogen gas 2 flows in the space S between the excimer UV lamp 1 and the protective tube 2. As shown in FIG. 1, excimer light is emitted in the emission direction from the outer peripheral surface of the excimer UV lamp 1.

Excimer light E1 emitted from the surface of the excimer UV lamp 1 facing the irradiation object A passes through the protective tube 2 without being absorbed by the nitrogen gas 2 in the space S. A is directly irradiated. Excimer light E2 emitted to the back side of the other excimer UV lamp 1 is
The light is reflected by the reflector 4 toward the irradiation object A,
Irradiation is performed on the irradiation target A through the substrate.

As a result, the irradiation amount on the irradiation target A can be increased with a simple structure while preventing the attenuation of the excimer light. Therefore, for example, JP-A-7-288109 and JP-A-8-
A container having a thick wall or a thick flat irradiation window as disclosed in JP-A-124540 is not required, the manufacturing cost can be reduced only in that portion, and it is economical. It is possible to approach, the irradiation efficiency of excimer light is increased, and the cleaning efficiency can be improved.

Further, when it is necessary to arrange a plurality of excimer UV lamps 1 in parallel according to the size of the irradiation object A, for example, as shown in FIG. No thick wall of the container as disclosed in JP-A-8-124540 or JP-A-8-124540 is required, and the electrodes 1a and 1b of the excimer UV lamps 1... Below, the illuminance distribution on the irradiation target A can be made more uniform. In particular, those shown in FIG. 3 are disclosed in, for example, JP-A-7-288109 and JP-A-8-
Since the space S through which the nitrogen gas 3 flows is isolated for each of the excimer UV lamps 1 and the amount of each of the excimer UV lamps 1 is smaller than that in which a plurality of excimer UV lamps 1 are arranged in parallel as disclosed in There is an advantage that the replacement with the gas 3 can be performed in a short time.

Further, in the case of this embodiment, the protection tube 2
Is formed in a cylindrical shape, so it has excellent structural strength and can withstand nitrogen gas pressure sufficiently even when its thickness is reduced. as a result,
Excimer UV lamp 1 and irradiation object A and a plurality of excimer U
The V lamps 1 can be brought closer to each other.

Furthermore, in the case of this embodiment, the reflector 4
Is curved in an arc shape along the outer peripheral surface of the excimer UV lamp 1, and the curvature of the reflective surface 4a is changed such that most of the excimer light E2 emitted from the back side of the excimer UV lamp 1 facing the excimer UV lamp 1 is excimer light. Since the light source is expanded outside the UV lamp (1), the object A is directly irradiated without returning to the excimer UV lamp (1). As a result, the irradiation intensity and the irradiation area on the irradiation target A can be improved.

FIG. 4 shows another embodiment of the present invention. This is different from the embodiment shown in FIGS. 1 and 2 in that the protection tube 2 is formed in a polygonal cylindrical shape, and the other configuration is the embodiment shown in FIGS. Is the same as In the illustrated example, it is formed in a square cylindrical shape, but may be formed in a polygonal shape of a pentagon or more.

Therefore, the one shown in FIG.
Excimer light E1 emitted from the opposing surface side of the excimer UV lamp 1 opposing the irradiation object A in the same manner as in the embodiment shown in FIG.
Is directly irradiated onto the irradiation target A through the rectangular protective tube 2 without being absorbed by the nitrogen gas 2 in the space S, and the other excimer light E2 emitted to the back side of the excimer UV lamp 1 Is reflected by the reflector 4 toward the irradiation target A, and is irradiated to the irradiation target A through the rectangular protective tube 2.

As a result, the distance from the entire bottom surface of the protection tube 2 to the irradiation target A can be made uniform, and the portion facing the center of the bottom surface of the protection tube 2 located at the shortest distance from the electrodes 1a and 1b of the excimer UV lamp 1 Comparing A1 with the portion A2 facing the bottom end of the protective tube 2 distant therefrom, there is no large difference in the amount of attenuation of the excimer light as compared with the embodiment shown in FIGS. In particular, although the portion A2 facing the bottom end is separated from the electrodes 1a and 1b, it is irradiated with the excimer light reflected by the reflector 4, so that there is an advantage that the irradiation amount can be made substantially the same as a whole.

Although not shown, an excimer illuminating device having the structure shown in FIG. 4 is provided by connecting a plurality of excimer UV lamps 1 in parallel according to the size of the irradiation object A as shown in FIG. It may be arranged in a shape.

In the illustrated example, the reflecting plate 4 having at least the reflecting surface 4a mirror-finished with an aluminum plate is suspended and fixed to the holder 1c of the excimer UV lamp 1 via a hanger 4b. However, the present invention is not limited to this. Although not shown, the reflection plate 4 may be formed of a material other than aluminum, or may be stuck to the inner surface of the protection tube 2 so as to be immovably arranged and fixed.

[0029]

As described above, according to the first aspect of the present invention, the excimer UV lamp is provided in the space between the excimer UV lamp and the protective tube, and the reflector is provided to provide the excimer UV lamp. Excimer light emitted from the opposing surface side of the lamp is directly irradiated to the irradiated object through the protective tube without being absorbed, and excimer light emitted to the other back side is reflected by the reflector. Since the object to be irradiated is irradiated through the protective tube, the irradiation amount to the object to be irradiated can be increased while preventing the excimer light from being attenuated with a simple structure. Therefore, compared with the conventional apparatus which requires a thick-walled container and a thick flat irradiation window for the internal pressure of nitrogen gas, these thick-walled containers and a thick flat irradiation window are not required, and the manufacturing cost can be reduced and the economy can be reduced. In addition, the irradiation target can be approached to the excimer UV lamp, the irradiation efficiency of the excimer light increases, and the cleaning efficiency can be improved. Moreover, a plurality of excimer U
When the V lamps need to be arranged in parallel, a thick wall of the container is not required as compared with the conventional one in which the excimer UV lamp is arranged with the thick wall of the container interposed therebetween. The electrodes can be placed close to each other,
The illuminance distribution on the irradiation target can be made more uniform under high irradiation efficiency.

According to the second aspect of the present invention, in addition to the effect of the first aspect, the cylindrical protective tube has excellent structural strength, so that it can sufficiently withstand the nitrogen gas pressure even if its thickness is reduced. Therefore, the excimer UV lamp and the irradiation target or the plurality of excimer UV lamps can be closer to each other.

According to a third aspect of the present invention, in addition to the effect of the first or second aspect, most of the excimer light emitted from the back side of the excimer UV lamp is reflected by the reflecting surface of the reflector, and the excimer Since the irradiation object is directly irradiated without returning to the UV lamp, the irradiation intensity and the irradiation area on the irradiation object can be improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an excimer illuminating device showing one embodiment of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is a reduced vertical sectional view showing a case where a plurality of excimer UV lamps are arranged in parallel.

FIG. 4 is a partial vertical cross-sectional view of an excimer illumination device showing another embodiment of the present invention.

[Explanation of symbols]

A Exposed object E2 Excimer light emitted to the back side S Space 1 Excimer UV
Lamp 2 Protective tube 3 Nitrogen gas 4 Reflector 4a Reflecting surface

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5F004 AA16 BA20 BB05 BC08

Claims (3)

[Claims] 1. A nitrogen gas (3) is provided to replace air present around the excimer UV lamp (1),
In an excimer illuminator provided with a reflector (4) for reflecting excimer light emitted from the excimer UV lamp (1) toward the irradiation target (A), excimer light is provided on the outer periphery of the excimer UV lamp (1). A protective tube (2) formed in a tubular shape with a material having excellent permeability to the excimer U is provided.
A nitrogen gas (3) is caused to flow into a space (S) defined between the V lamp (1) and the protective tube (2), and excimer light (E) emitted to the back side of the excimer UV lamp (1) is emitted.
Reflector (4) so that 2) is reflected to irradiated object (A)
An excimer lighting device, comprising: 2. An excimer lighting device according to claim 1, wherein said protection tube is formed in a cylindrical shape. 3. The reflecting surface (4a) of the reflector (4) is concavely curved along the outer peripheral surface of the excimer UV lamp (1), and the curvature of the reflecting surface (4a) is changed to the excimer facing the excimer UV lamp (1). The excimer lighting device according to claim 1 or 2, wherein most of the excimer light (E2) emitted from the back side of the UV lamp (1) expands outside the excimer UV lamp (1).