JP2002263596A - Ultraviolet irradiation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the oxidation of the external electrode of an excimer lamp and other constituent parts thereof by ozone and to also efficiently cool the excimer lamp without using a lamp house high in airtightness or the like. SOLUTION: In the ultraviolet irradiation device 100, the cylindrical excimer lamp 104 is supported by a support means 102 arranged so as to cover the upper surface side of the excimer lamp. Nitrogen gas is ejected to the exposed surface of the excimer lamp during the operation of the excimer lamp from the nitrogen gas jet pipe 112 connected to a nitrogen gas supply source. The atmosphere around the excimer lamp 104 is substituted with the nitrogen gas ejected to the excimer lamp 104 to avoid such a phenomenon that ozone comes into contact with the external electrode to oxidize the same. Further, the cooling of the excimer lamp can be efficiently performed by directly spraying inert gas to the outer peripheral surface of the excimer lamp.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for radiating light in a vacuum ultraviolet region and for cleaning or modifying the surface of a semiconductor wafer or a glass substrate by using the synergistic action of the light and ozone. The present invention relates to an ultraviolet light irradiation device.

[0002]

2. Description of the Related Art The allowable level of organic compound contamination of a semiconductor or a liquid crystal substrate has become more severe with the further miniaturization of the processing. For these reasons, in these manufacturing processes, in recent years, the technology of light cleaning or light reforming has attracted attention. In the light cleaning or light reforming, a workpiece is irradiated with vacuum ultraviolet light for a predetermined time, and an organic compound attached to the surface is cleaned or surface modified by a photochemical reaction.

In recent years, attention has been paid to excimer lamps as light sources used in these applications, and their introduction to production lines has already begun. In particular, a xenon excimer lamp in which xenon is sealed emits light having a wavelength of 172 nm, which is vacuum ultraviolet light. Therefore, when irradiated in an atmosphere containing oxygen, oxygen molecules (O ₂ ) absorb the light and oxygen atoms (O 2 ) And ozone (O ₃ ). The photon energy of light at 172 nm is about 7.2 eV, which is larger than the binding energy of many organic compounds.

[0004] In each production process of a semiconductor device, there is a high probability that a silicon substrate is contaminated with an organic compound. Similarly, in a glass substrate in the field of liquid crystal, the contamination by an organic compound in each process hinders improvement in quality. Therefore, by irradiating 172nm light, it is possible to cut chemical bonds of various organic compounds, which are the causes of contamination of various substrates, and to efficiently oxidize and decompose them from various substrates by the generated active oxygen species. It is.

[0005]

As described above, an excimer lamp is very effective for light cleaning and light reforming. On the other hand, in light cleaning and light reforming using an excimer lamp, the following two methods are required. There were two major issues.

(1) As described above, in the light cleaning and light reforming using the excimer lamp, ozone is generated around the excimer lamp, and this easily oxidizes the external and internal electrodes of the lamp house and the lamp. Would. Oxidation of these components shortens product life and leads to performance degradation.

(2) Excimer lamps have a capacity of 7 to 10 k.
V, a high voltage of about 100 kHz to 3 MHz is applied. When the temperature of the excimer lamp rises, the light conversion efficiency with respect to the power supplied to the lamp decreases.

As means for solving such a problem, the following is conventionally known. That is, mainly
In order to prevent oxidation of internal parts, excimer lamps
It is housed in a sealed container or lamp house equipped with ultraviolet light transmitting glass, and nitrogen or other inert gas is introduced or filled into the container, thereby preventing the contact of the electrodes and other parts of the excimer lamp with ozone. are doing.

However, when such a method is used, the hermetic container or the lamp house is required to have high airtightness. That is, if the airtightness of the container is not reliably maintained, the gas in the container is not completely replaced by the inert gas, thereby generating ozone and oxidizing and corroding the external and internal electrodes. There is.

[0010] The requirement for very high airtightness of the container is
Difficulty often occurs in design. For example, since a high voltage needs to be applied to an excimer lamp as described above, a container or a lamp house needs to have a structure with high pressure resistance and high airtightness, resulting in an increase in the size of the apparatus and an increase in cost. Particularly, a quartz glass plate generally used as an ultraviolet light transmitting glass (for example, width: 100 mm, length: 1000 mm, thickness: 2 to 3 m
In order to attach m) to the container in a highly airtight manner using an O-ring or the like, a great deal of labor and cost are required.

In a structure in which an excimer lamp is housed in a sealed container or a lamp house, an object to be irradiated is irradiated with ultraviolet light from the excimer lamp through the ultraviolet light transmitting glass. However, there is a problem that the cleaning efficiency with respect to the energy dropped into the device decreases. Further, the distance between the excimer lamp and the irradiation target cannot be reduced to a certain value or less due to the presence of the ultraviolet light transmitting glass, and the amount of light reaching the irradiation target is attenuated. Is proportional to the square of the distance).

Conventionally, a cooling liquid such as water or a cooling gas such as nitrogen gas is passed through an inner tube of the excimer lamp for the purpose of cooling the excimer lamp. However,
In the case of flowing a liquid such as water into the inner tube, the excimer lamp is required to have a specially configured excimer lamp, although the cooling efficiency of the excimer lamp is excellent. In such a case, it is difficult to efficiently cool the entire excimer lamp, and in order to achieve the entire cooling, a considerable amount of nitrogen is required to flow, resulting in a high cost of consuming nitrogen gas. is there.

Accordingly, an object of the present invention is to provide an ultraviolet light irradiation apparatus which can prevent the external and internal electrodes from being oxidized by ozone with a relatively simple structure without enclosing the excimer lamp in a closed container. It is in.

Another object of the present invention is to provide an ultraviolet light irradiation apparatus which can efficiently cool an excimer lamp with a relatively simple structure.

[0015]

In order to achieve the above object, an ultraviolet light irradiation apparatus of the present invention applies a high voltage to a discharge gas sealed in a space between an inner tube and an outer tube, and A cylindrical excimer lamp for irradiating ultraviolet light to the outside of the outer tube, a support means arranged to cover an upper surface side of the excimer lamp, and supporting the excimer lamp; And an inert gas jetting means for covering the exposed surface with the inert gas during the irradiation of the excimer lamp with ultraviolet light.

According to the above configuration, during the irradiation of the ultraviolet light, the upper surface of the excimer lamp is covered by the supporting means, while the lower surface exposed to the outside air is ejected from the inert gas ejecting means. Ozone is prevented from contacting and oxidizing the external electrode of the excimer lamp because it is covered with the inert gas. Further, by blowing the inert gas directly onto the outer peripheral surface of the excimer lamp, the cooling can be efficiently performed.

In the present invention, the inert gas ejecting means is a pair of inert gas ejecting pipes arranged on both sides of the excimer lamp along the axial direction thereof, and each inert gas ejecting pipe is provided with an inert gas ejecting pipe. It is preferable that the apparatus is provided with one or more inert gas ejection ports along the longitudinal direction, and an inert gas supply source for supplying an inert gas to the inert gas ejection pipe.

In this case, it is preferable that the direction of the jet port of the inert gas jet pipe is oriented toward the axis of the excimer lamp or in the range of 20 to 60 degrees with respect to a horizontal plane.

As the inert gas supplied by the inert gas jetting means, nitrogen, argon, helium gas or the like, which hardly absorbs light, can be used. In view of the cost, nitrogen gas is preferably used. Can be

In a preferred embodiment of the present invention, the support means has a concave portion conforming to the shape of the upper surface of the excimer lamp, and the upper surface of the excimer lamp is accommodated in the concave portion. Supports the excimer lamp.

More preferably, at least a region including the concave portion of the support means is made of a metal material, and the excimer lamp is supported with the upper surface of the excimer lamp substantially in close contact with the concave portion. ADVANTAGE OF THE INVENTION According to the structure of this invention, the cooling efficiency of an excimer lamp can be improved further and highly efficient ultraviolet irradiation can be achieved.

In this case, it is preferable that the concave surface of the supporting means covers substantially the upper half of the excimer lamp.

In a preferred embodiment of the present invention, the ultraviolet irradiation device is disposed on both sides of the excimer lamp along the axial direction of the excimer lamp, and emits the inert gas ejected from the inert gas ejection pipe to the excimer lamp. And a pair of reflectors leading to the exposed surface.

[0024] In a preferred embodiment, the reflecting plate includes:
It has a function of reflecting ultraviolet light emitted from the excimer lamp toward an object to be irradiated.

In this case, it is preferable that the reflecting plate is attached to the supporting means on both sides of the concave portion.

In another embodiment of the present invention, an ultraviolet light transmitting plate is provided below the excimer lamp and the inert gas ejection pipe, and the ultraviolet light from the excimer lamp is transmitted through the ultraviolet light transmitting plate. The object to be irradiated can be irradiated.

In this case, in the excimer lamp,
It is preferable to dispose the inert gas ejection pipe in a region substantially surrounded by the reflection plate and the ultraviolet light transmission plate. Such an arrangement improves the efficiency with which the inert gas reaches the excimer lamp.

In the present invention, it is preferable that, of the external electrodes provided on the outer peripheral surface of the outer cylindrical tube of the excimer lamp, a region which fits in the concave portion of the support means is formed in a plate shape. Thereby, the heat radiation efficiency from the excimer lamp to the supporting means is improved.

The internal electrodes provided on the inner peripheral surface of the inner tube of the excimer lamp may be plate-shaped.

Further, the ultraviolet light irradiation apparatus of the present invention sprays an inert gas toward the inner surface of the inner tube of the excimer lamp, whereby the inner tube is irradiated with ultraviolet light from the excimer lamp. And a second inert gas jetting means for covering the inner surface of the substrate with the inert gas. This can prevent oxidation of the internal electrode disposed in the inner tube by ozone, and can more efficiently cool the excimer lamp.

In this case, the second inert gas jetting means is disposed along the inner tube of the excimer lamp, and is provided with a plurality of inert gas jetting ports around it. It is preferred to have a pipe.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on one embodiment shown in the drawings. 1 and 2 are views showing an ultraviolet light irradiation device according to an embodiment of the present invention, and are a cross-sectional view in a front direction and a side view with a part thereof cut away. In the figure, the ultraviolet light irradiation device 100 includes a cylindrical excimer lamp 104 on the lower surface side of a lamp support block 102 having a convex cross section.

The excimer lamp 104 irradiates ultraviolet light by applying a high voltage to a discharge gas sealed in a generally known double tube. In one embodiment, an outer cylindrical tube 104a made of a quartz glass tube having a thickness of 1.5 mm and a length of 30 cm, and an inner tube made of a quartz glass having a smaller diameter and also having a thickness of 1.5 mm and a length of 30 cm. A tube in which the cylindrical tubes 104b are arranged concentrically, both ends of both the cylindrical tubes are sealed, and a xenon gas is sealed in a space 104c formed thereby is preferably used. On the outer surface of the outer tube 104a, an external electrode 104d through which mesh-like light passes is provided, and on the inner surface of the inner tube 104b, a spiral-shaped inner electrode 104e is arranged. A power supply 200 (FIG. 2) is provided between the electrodes.
By applying a high voltage from the
Excimer light of 72 nm is emitted outside the outer tube.

The lamp support block 102 has a shape along the upper half of the excimer lamp 104 along the longitudinal center of the lower surface thereof, that is, a half pipe-shaped support surface 102a.
Having. The excimer lamp 104 is mounted on the support surface 102a with its outer peripheral surface in contact with the support surface 102a.
The upper half of the excimer lamp 104 is fixed at the both ends in the longitudinal direction of the excimer lamp 104 as shown in FIG.
Is fixed to the block.

The bearing surface 102a has basically two functions. The first function of the bearing surface 102a is to prevent vacuum ultraviolet light from being emitted from the upper half of the excimer lamp 104 to the outside. As a result, ozone is not generated around the upper half of the excimer lamp 104, so that oxidation of the external electrode 104d disposed in this region is prevented. The second function of the bearing surface 102a is to achieve efficient heat dissipation by contacting the bearing surface 102a with the outer surface of the upper half of the excimer lamp 104. As described above, the excimer lamp 104
Since a high voltage of about 10 to 10 kV and about 100 kHz to 3 MHz is applied, the excimer lamp becomes extremely high during use. Bearing surface 1 of lamp bearing block as in this embodiment
Since 02a is in surface contact over the entire upper half of the excimer lamp 104, heat from the excimer lamp 104 is efficiently transmitted to the lamp support block 102 side. For the purpose of making this function effective, the lamp support block 102 is preferably made of a material having relatively high thermal conductivity, for example, aluminum, a stainless alloy (such as SUS304), or other metals.

The ultraviolet light irradiation device 100 according to this embodiment
Further comprises an ultraviolet light transmitting glass 106 and a reflector 10
8 is provided. The ultraviolet light transmitting glass 106 is provided below the excimer lamp 104 as shown in the figure, and the object to be irradiated is irradiated with ultraviolet light from the excimer lamp 104 through the glass. Here, since the excimer lamp 104 has its upper half covered by the lamp support block 102 and only the lower half is exposed to the outside, ultraviolet light is irradiated downward from the exposed region. The Rukoto. The ultraviolet light transmitting glass 106 has glass support arms 110 suspended from both sides of the lamp support block 102.
Is supported immediately below the excimer lamp 104,
In FIG. 1, the space surrounded by the lamp support block 102, the glass support arm 110, and the ultraviolet light transmitting glass 106 escapes in the direction of the plane of the paper, and is thus exposed to the outside air without being sealed. .
In a preferred embodiment, quartz glass having a width of 100 mm, a length of 330 mm, and a thickness of 1 mm can be used as the ultraviolet light transmitting glass 106.

However, it should be noted that, when the present invention is realized, the space surrounding the excimer lamp 104 does not need to be sealed from the outside air, as described later, so that the ultraviolet light transmitting glass is not necessarily required. When the ultraviolet light transmitting glass 106 is not provided, the attenuation at the time of transmission is eliminated, and the distance between the excimer lamp and the object to be irradiated can be reduced, so that more efficient light cleaning and light reforming can be performed. Become.

The reflector 108 is mounted on the lamp support block 102 on both sides of the excimer lamp 104 as shown in FIG. The lower surface side of the reflector 108 is mirror-finished, and functions to efficiently reflect ultraviolet light from the excimer lamp 104 and guide it to an object to be irradiated. In one embodiment, the reflector 108 is formed by mirror-finish an aluminum plate having a thickness of about 1.5 mm. The reflector 108 also has a function of guiding nitrogen gas ejected from a nitrogen gas ejection pipe 112 described later toward an exposed surface of the excimer lamp 104.

The ultraviolet light irradiation apparatus 100 further includes nitrogen gas supply means for ejecting nitrogen gas to the exposed surface of the excimer lamp 104, which comprises a pair of nitrogen gas ejection pipes 112, a mass flow controller 114, and a nitrogen gas supply. A source 116 is included.

The pair of nitrogen gas ejection pipes 112 is shown in FIG.
As shown in the figure, on both sides of the excimer lamp 104 along the axial direction, it is installed in a space between the ultraviolet light transmitting glass 106 and the reflector 108. Each of the nitrogen gas ejection pipes 112 has a large number of ejection ports 112a opened in a line at regular intervals along the longitudinal direction thereof, and these are directed to the outer surface of the excimer lamp 104.
The nitrogen gas supplied from the nitrogen gas supply source 116 has a constant flow rate (for example,
After the flow rate is adjusted, the gas is supplied to both nitrogen gas ejection pipes 112, and is ejected from each ejection port 112a toward the excimer lamp 104. Excimer lamp 10
The nitrogen gas ejected toward 4 covers the exposed light emitting surface. That is, the external electrode 104d provided on the outer tube surface of the excimer lamp 104 is
During the lighting of 4, it is placed in a nitrogen gas atmosphere. Therefore, the ozone generated by the lighting of the excimer lamp 104 does not touch the external electrode 104d, thereby preventing the oxidation of the external electrode 104d. Also, the blown nitrogen gas effectively cools the lower half of the lamp. In particular, in the present embodiment, the nitrogen gas ejection pipe 112 is connected to the excimer lamp 1.
Since the nitrogen gas is ejected into the space substantially surrounded by the reflector 04, the reflector 108 and the ultraviolet light transmitting glass 106, the space is easily maintained in a nitrogen atmosphere, and the arrival rate of the nitrogen gas to the surface of the excimer lamp 104 is reduced. improves.

Each nitrogen gas ejection pipe 112 is oriented so that its ejection port 112a can eject nitrogen gas to the excimer lamp 104 efficiently. In a preferred embodiment, the direction of the spout 112a is from 20 degrees to the horizontal plane.
The range is 60 degrees, particularly preferably 30 degrees, and the direction may be set so as to face the axis of the excimer lamp 104.

As described above, each nitrogen gas ejection pipe 112
A reflector 108 is provided at the upper part of the excimer lamp 104 and functions to efficiently guide the nitrogen gas ejected from each nitrogen gas ejection pipe 112 to the surface of the excimer lamp 104. Since the surface of the reflector 108 is placed in a nitrogen gas atmosphere as a result,
Its oxidation is prevented.

FIG. 3 is a sectional view and a side view showing an example of the nitrogen gas ejection pipe 112. As shown in the figure, one end of the nitrogen gas ejection pipe 112 is open and the other end is closed. At this open end, a nitrogen gas supply source 116 is provided.
Connect a nitrogen gas supply pipe (not shown) connected to
By supplying nitrogen gas toward the closed other end, nitrogen gas is ejected from a large number of ejection ports 112a opened in a line on the side surface. In a preferred embodiment, the nitrogen gas ejection pipe 112 has a length of 300 mm and an outer diameter of 30 mm.
390mm in length and 3m in outer diameter for the excimer lamp
m, stainless steel pipe with inner diameter 2mm, pitch 5mm
In this case, the one provided with about 60 circular ejection ports 112a having a diameter of 0.3 mm can be used.

However, the nitrogen gas ejection pipe 112 is
It may have a structure in which both ends are opened so that nitrogen gas can be supplied from both ends thereof, and a single width of a single width (for example, 0.3 to 0.5 mm) is used as a nitrogen gas ejection port. A slit may be formed, and nitrogen gas may be ejected from the slit.

In the embodiment of the ultraviolet light irradiation device shown in FIG. 1, the external electrode 104d of the excimer lamp 104 is formed in a mesh. However, since the upper half of the excimer lamp 104 does not need to transmit ultraviolet light to the outside, it can be configured with a plate-shaped external electrode 400 as shown in FIG. Plate-shaped external electrode 400
Is formed in a semicircular shape along the upper half of the excimer lamp 104 and the bearing surface 102a of the lamp bearing block 102,
Adheres to both when attached. Thereby, the heat radiation efficiency of the excimer lamp 104 is further improved. Further, ultraviolet light radiated upward from the excimer lamp 104 is reflected by the plate-shaped external electrode 400,
Ultraviolet light radiated from the lower side of the excimer lamp to the outside can be increased. The upper half of the external electrode is shown in FIG.
, And the lower half of the plate has a mesh shape.

The internal electrode of the excimer lamp 104 can be a cylindrical plate-shaped internal electrode 500 as shown in FIG. 5 instead of a spiral-shaped internal electrode. The cylindrical plate-shaped internal electrode 500 has an outer diameter slightly larger than the inner diameter of the inner cylindrical tube 104b of the excimer lamp when no external force is applied, and has a slit 500a along the entire axial direction thereof.
Are formed. The internal electrode 500 is
The diameter of the excimer lamp is reduced by applying an external force and inserted into the inner tube 104b of the excimer lamp, and the internal force is reduced by releasing the external force. It comes into close contact with the inner surface of the cylindrical tube 104b. Thus, the internal electrode 50
The excimer lamp 1 is constituted by forming a cylindrical plate
The ultraviolet light radiated from the liquid crystal 04 is reflected thereby, and the vacuum ultraviolet light can be guided to the outside more efficiently. Further, since the cylindrical plate-shaped internal electrode 500 is provided in close contact with the inner cylindrical tube 104b of the excimer lamp, it is possible to prevent micro-discharge that may occur when a high voltage is applied between the electrodes.

FIG. 6 shows another embodiment of the ultraviolet light irradiation apparatus according to the present invention. The ultraviolet light irradiation device 600 according to the present embodiment is configured to further include a nitrogen gas ejection pipe 602 in the excimer lamp 104 of the ultraviolet light irradiation device in the previous embodiment. In the present embodiment, the same components as those in the previous embodiment are denoted by the same reference numerals, and description thereof is omitted.

As shown in the figure, the nitrogen gas ejection pipe 602 is located at the center of the excimer lamp 104, that is, the inner cylinder 1
04b is installed along its axis. The nitrogen gas ejection pipe 602 is provided with a nitrogen gas ejection port 602a over substantially the entire peripheral surface thereof. One end of the nitrogen gas ejection pipe 602 is connected to the nitrogen gas supply source 116 via the mass flow controller 114, and the flow rate of the supplied nitrogen gas (for example, 3 to 5 L / min) is supplied thereto. Is a nitrogen gas ejection pipe 602
Are ejected toward the inner surface of the inner tube 104b from the respective ejection ports 602a. Thereby, the inside of the excimer lamp 104 can be efficiently cooled. Although the inner electrode 104e is disposed on the inner wall surface of the inner tube 104b as described above, the supply of nitrogen gas replaces the oxygen-containing air present in the inner tube 104b with the nitrogen gas. Therefore, generation of ozone due to ultraviolet light emitted from the excimer lamp is eliminated, and oxidation of the internal electrodes due to ozone is prevented. In a preferred embodiment, this nitrogen gas ejection pipe 6
Reference numeral 02 denotes a stainless steel pipe having an outer diameter of 3 mm and an inner diameter of 2 mm, which is closed on one side, and a jet port 602 a having a diameter of 0.1 mm is opened at a pitch of 3 mm over substantially the entire surface of the pipe. Note that, similarly to the nitrogen gas ejection pipe 112 outside the excimer lamp, the nitrogen gas ejection pipe 602 may have a structure in which both ends are opened so that nitrogen gas can be supplied from both ends.

The embodiment of the present invention has been described with reference to the drawings. However, it is apparent that the present invention is not limited to the matters described in the above embodiments, and that changes, improvements, and the like can be made based on the description in the claims. In each of the above embodiments, the excimer lamp is not sealed off from the outside, but if necessary, the excimer lamp or other components may be housed in a sealed container or a lamp house. good.

In practicing the present invention, the excimer lamp is mounted on the lamp support block by a method other than the method using a fixed band, for example, by placing the excimer lamp in a cap-shaped receiving portion in which both ends of the excimer lamp are fixed to the lamp support block. It can be fixed by fitting or the like. Also, the nitrogen gas ejection pipe may be installed at a position that does not prevent the ultraviolet light from the excimer lamp from reaching the irradiation object,
It is not limited to the arrangement of the above embodiment.

[0051]

As described above, according to the present invention, the oxidation of the external electrodes and other components of the excimer lamp by ozone can be prevented without using a highly airtight lamp house or the like. It can be cooled very efficiently. The ultraviolet light irradiation device configured based on the present invention can be manufactured at low cost because the device configuration is relatively simple.

[Brief description of the drawings]

FIG. 1 is a sectional view in the front direction of an ultraviolet light irradiation device according to an embodiment of the present invention.

FIG. 2 is a side view showing a part of the ultraviolet light irradiation device of FIG.

FIG. 3 is a cross-sectional view and a side view showing an example of a nitrogen gas ejection pipe.

FIG. 4 is a perspective view showing a plate-like external electrode.

FIG. 5 is a perspective view showing a cylindrical plate-like internal electrode.

FIG. 6 is a front sectional view showing another embodiment of the ultraviolet light irradiation device according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 Ultraviolet light irradiation apparatus 102 Lamp support block 102a Bearing surface 104 Excimer lamp 104a Outer tube 104b Inner tube 104c Space 104d Outer electrode 104e Inner electrode 106 Ultraviolet light transmitting glass 108 Reflector 110 Glass support arm 112 Nitrogen gas ejection pipe 112a Spout 114 Mass flow controller 116 Nitrogen gas supply source 200 Power supply 202 Fixed band 400 Plate external electrode 500 Cylindrical plate internal electrode 500a Slit 600 Ultraviolet light irradiation device 602 Nitrogen gas ejection pipe 602a Spout

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // F21V 29/00 H01L 21/302 N

Claims (16)

[Claims] 1. A cylindrical excimer lamp for applying a high voltage to a discharge gas sealed in a space between an inner tube and an outer tube to irradiate ultraviolet light outside the outer tube; A support means arranged to cover the upper surface side of the excimer lamp, and supporting the excimer lamp; and spraying an inert gas toward an exposed surface of the excimer lamp, thereby irradiating ultraviolet light from the excimer lamp. And an inert gas jetting means for covering the exposed surface with the inert gas. 2. The inert gas ejecting means is a pair of inert gas ejecting pipes arranged on both sides of the excimer lamp along an axial direction of the excimer lamp. 2. The ultraviolet according to claim 1, further comprising: one provided with one or a plurality of outlets of the inert gas along the line, and an inert gas supply source for supplying an inert gas to the inert gas ejection pipe. 3. Light irradiation device. 3. The ultraviolet light irradiation apparatus according to claim 2, wherein the direction of the discharge port of the inert gas discharge pipe is directed to the axis of the excimer lamp. 4. The ultraviolet light irradiation device according to claim 2, wherein the direction of the jet port of the inert gas jet pipe is in a range of 20 degrees to 60 degrees with respect to a horizontal plane. 5. The excimer lamp according to claim 1, wherein the supporting means has a concave portion along the shape of the upper surface of the excimer lamp, and supports the excimer lamp in a state where the upper surface of the excimer lamp is accommodated in the concave surface. 5. The ultraviolet light irradiation device according to any one of items 1 to 4, 6. The excimer lamp according to claim 5, wherein a region including at least the concave portion of the support means is made of a metal material, and the excimer lamp is supported in a state where the upper surface side of the excimer lamp is substantially in close contact with the concave portion. Ultraviolet light irradiation device. 7. The ultraviolet light irradiation device according to claim 5, wherein the concave portion of the supporting means covers a substantially upper half of the excimer lamp. 8. The apparatus further comprises a pair of reflectors disposed on both sides of the excimer lamp along an axial direction thereof and guiding an inert gas ejected from the inert gas ejection pipe to an exposed surface of the excimer lamp. The ultraviolet light irradiation device according to claim 2. 9. The ultraviolet light irradiation device according to claim 8, wherein the reflection plate has a function of reflecting ultraviolet light emitted from the excimer lamp toward an object to be irradiated. 10. The ultraviolet light irradiation device according to claim 8, wherein the reflector is attached to the supporting means on both sides of the concave portion. 11. An ultraviolet light transmitting plate below the excimer lamp and the inert gas ejection pipe, and irradiates an object to be irradiated with ultraviolet light from the excimer lamp via the ultraviolet light transmitting plate. The ultraviolet light irradiation device according to any one of 2 to 10. 12. The ultraviolet light irradiation device according to claim 11, wherein the inert gas ejection pipe is disposed in a region substantially surrounded by the excimer lamp, the reflection plate, and the ultraviolet light transmission plate. 13. The ultraviolet light according to claim 5, wherein a region of the external electrode provided on the outer peripheral surface of the outer cylindrical tube of the excimer lamp, which is accommodated in the concave portion of the support means, has a plate shape. Irradiation device. 14. An internal electrode provided on an inner peripheral surface of an inner tube of the excimer lamp has a plate-like shape.
4. The ultraviolet light irradiation device according to any one of 3. 15. An inert gas is sprayed toward the inner surface of the inner tube of the excimer lamp, thereby covering the inner surface of the inner tube with the inert gas during irradiation of ultraviolet light from the excimer lamp. The ultraviolet light irradiation device according to claim 1, further comprising a second inert gas ejection unit. 16. The inert gas jetting means is arranged along an inner tube of the excimer lamp and has an inert gas jetting pipe having a plurality of the inert gas jetting ports around the second inert gas jetting means. The ultraviolet light irradiation device according to claim 15, comprising: