KR100734127B1 - Excimer lamp - Google Patents

Abstract

It is an object of the present invention to provide an excimer lamp having a novel structure in which the structure is simple and there is no breakage caused by thermal expansion in the discharge vessel, and the discharge is stably generated.

A discharge container made of a material which transmits ultraviolet rays and in which a gas for discharge is sealed, an inner electrode which extends the inside of the discharge container in the longitudinal direction and is hermetically sealed at the end of the discharge container, and on the outer surface of the discharge container. In the excimer lamp which consists of the outer electrode arrange | positioned, the said inner electrode is covered with the inner surface which consists of a dielectric material whose at least one outer surface of the site | part which discharges between at least an outer electrode is opened in discharge space. It is characterized by being.

Description

Excimer lamp {EXCIMER LAMP}

1 is a diagram showing Embodiment 1 of an excimer lamp of the present invention;

2 is a diagram showing Embodiment 2 of an excimer lamp of the present invention;

3 is an enlarged view illustrating main parts of FIG. 1;

4 is an enlarged view illustrating main parts of FIG. 2;

5 is a diagram showing Embodiment 3 of an excimer lamp of the present invention;

6 is a diagram showing a fourth embodiment of an excimer lamp of the present invention;

7 is a diagram showing a fifth embodiment of an excimer lamp of the present invention;

8 shows a sixth embodiment of an excimer lamp of the present invention;

9 is a diagram showing a seventh embodiment of an excimer lamp of the present invention;

10 is a diagram showing an irradiation device using an excimer lamp of the present invention;

11 is a view showing a conventional excimer lamp,

It is a figure which shows another conventional example.

<Explanation of symbols for main parts of drawing>

1: excimer lamp 2: inner electrode

3: outer electrode 10 discharge vessel

11 light emitting part 12 sealing part                 

21: elastic portion 22: inner tube

30 support member 100 recessed part (fixing means)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an excimer lamp for discharging excimer light through a dielectric material, and more particularly to an excimer lamp having an internal electrode in a discharge space.

As a technique related to the present invention, there is, for example, Japanese Patent Laid-Open No. 2-7353, in which a discharge vessel is filled with a discharge gas for forming excimer molecules, and a dielectric barrier discharge (aka, ozoneizer discharge, or silent discharge) is provided. An excimer molecule is formed by the Electrical Society published revised edition "Discharge Handbook", June 1989, 7th Printing, page 263), and the emitter which extracts light emitted from this excimer molecule, ie, an excimer lamp, is described. German Patent Laid-Open Publication DE4022279A1 discloses an excimer lamp for lighting in units of MHz, and also describes "Silent discharge for the generation of ultraviolet and vacuum ultraviolet excimer radiation" (Pure & Appl. Chem., Vol. 62, No. 9). , pp. 1667-1674, 1990, discloses an excimer lamp (also called a dielectric barrier discharge lamp) which is lit at 50 MHz at several MHz.

These excimer lamps have an entire cylindrical shape in a discharge vessel, and at least a portion of the discharge vessel also serves as a dielectric for performing discharge (dielectric barrier discharge) interposed through a dielectric material, and at least a portion of the dielectric radiates from excimer molecules. It is transmissive to the vacuum ultraviolet light (light having a wavelength of 200 nm or less), and a mesh electrode is provided on the outer surface of the discharge vessel as one electrode.

Such excimer lamps have various features that are not found in conventional low-pressure mercury discharge lamps and high-pressure discharge lamps, for example, strongly radiate ultraviolet light of a single wavelength. The light emitting device using the excimer lamp is, for example, Japan. Japanese Patent No. 2854255, Japanese Patent Laid-Open No. 2002-168999, and the like.

The excimer lamp (dielectric barrier discharge lamp) disclosed in Japanese Patent No. 2854255 and Japanese Patent Laid-Open No. 2002-168999 has a double cylindrical shape in which a cylindrical outer tube is coaxially arranged outside the cylindrical inner tube. The inner electrode is arranged inside the inner tube, the outer electrode is disposed on the outer surface of the outer tube, and the space formed between the inner tube and the outer tube is used as the discharge space.

11 shows a schematic configuration of a double cylindrical excimer lamp. (a) shows the whole cross section, and (b) shows the A-A cross section of (a).

The excimer lamp 1 is cylindrical in overall shape and is made of synthetic quartz glass. The discharge lamp 1 is arranged between the outer tube 51 and the inner tube 52 because the outer tube 51 and the inner tube 52 are arranged coaxially to form a double cylindrical tube and both ends are closed. The discharge space is formed in the. In the discharge space, an excimer molecule is formed by dielectric barrier discharge, and a discharge gas such as xenon gas, which emits vacuum ultraviolet light from the excimer molecule, is enclosed. For example, the discharge lamp 1 has a total length of 800 mm, an outer diameter of 27 mm, an outer diameter of the inner tube 52 of 16 mm, a thickness of the outer tube 51 and the inner tube 52 of 1 mm, and 400W. Lights up.

An inner electrode 2 serving as one electrode is provided on the inner surface of the inner tube 52, and a mesh shaped outer electrode 3 serving as the other electrode is provided on the outer surface of the outer tube 51. The inner electrode 2 is in the form of a pipe, and the outer electrode 3 is configured seamlessly and has elasticity as a whole, so that the adhesion of the outer tube 51 can be improved.

An alternating current power source (not shown) is connected between the inner electrode 2 and the mesh electrode 3, whereby excimer molecules are formed in the discharge space to emit ultraviolet light. When xenon gas is used as the gas for discharge, light of wavelength 172nm is emitted.

By the way, this excimer lamp of the double cylindrical structure has the following problem.

First, since the two quartz glass tubes of an inner side pipe | tube and an outer side pipe are made into double cylinders, the whole discharge container becomes large. In addition, since the inner tube is welded and supported at the end, it is likely to be damaged under the influence of gravity.

Secondly, a manufacturing process for joining two quartz glass tubes at both ends is required, which is complicated and complicated.

Third, the inner tube has a higher temperature than the outer tube that can be cooled, and is subjected to a large load due to thermal expansion, and in particular, the stress is concentrated at the junction with the outer tube, and it is easy to break. Serious.

Moreover, there exists an excimer lamp which is not a double cylinder but has a structure formed so that an inner electrode may extend in the discharge space. For example, Japanese Patent Laid-Open No. 8-508363 and Japanese Laid-Open Patent Publication No. 2003-317670 are disclosed.

Fig. 12 shows the structure of the conventional example. In this structure, the discharge vessel 60 consists of one cylindrical body, and in the discharge space in the discharge vessel 60, the inner electrode 61 extends in the axial direction, and on the outer surface of the discharge vessel 60 The outer electrode 62 is provided.

According to the above structure, since there is no equivalent to the inner tube in the double cylindrical one, some of the problems of the double cylindrical structure can be solved.

However, since the inner electrode is exposed in the discharge space, there is a problem that direct discharge occurs in the inner electrode, the inner electrode tends to deteriorate, and the discharge becomes unstable. In addition, the deteriorated electrode components are discharged into the discharge space, causing sputtering in the discharge vessel, which results in premature illumination degradation. Moreover, since it discharges directly to an inner electrode, the temperature of an inner electrode and a gas for discharge tends to rise, and as a result, luminous efficiency also falls easily.

In addition, since the dielectric material exists only in the vicinity of one electrode, when the AC is turned on, the balance of the discharge is broken on both the positive and negative sides.

In addition, when the polarity of the feed to the electrode is not paid attention, arc-like discharge is generated and excimer light emission is not produced efficiently. Once the arc-like discharge is formed, the part is glowing and the electrode is broken. There is another problem.

<Patent Document 1> Japanese Patent Laid-Open No. 2-7353

<Patent Document 2> Japanese Patent No. 2854255                         

<Patent Document 3> Japanese Patent Laid-Open No. 2002-168999, etc.

<Patent Document 4> Japanese Patent Application Laid-Open No. 8-508363

<Patent Document 5> Japanese Patent Laid-Open No. 2003-317670

The problem to be solved by the present invention is to eliminate the complexity of the structure of the double-cylindrical excimer lamp, and also to eliminate the problem of the discharge of the excimer lamp having a structure in which the inner electrode is directly exposed in the discharge space, the inner electrode in the discharge space An excimer lamp having a novel structure covered by a dielectric having an open end is provided.

The excimer lamp of the present invention is composed of a dielectric material that transmits ultraviolet rays and is filled with a gas for discharge therein, and the inside of the discharge vessel extends in the longitudinal direction and is airtight at the end of the discharge vessel. In the structure which consists of the inner electrode sealed so that the outer electrode arrange | positioned on the outer surface of a discharge container, the outer surface of the site | part which discharges between at least one outer electrode is at least one end inside a discharge container at least. It is characterized by being covered by an inner tube made of an open dielectric material.

Further, both ends of the inner tube are open in the discharge space.

Further, the inner tube is supported by the discharge vessel by the support member.                     

Moreover, the said support means is attached to an inner side pipe | tube, and the discharge container is provided with the fixing means which regulates the movement to the longitudinal direction of this support member, It is characterized by the above-mentioned.

The inner tube is supported by the inner electrode.

Alternatively, one end of the inner tube is opened in the discharge space, and the other end is connected to the discharge vessel.

Alternatively, the inner electrode is sealed at both ends of the discharge vessel, and at least a portion thereof is formed with an elastic portion that is stretchable in the longitudinal direction.

1 shows a first embodiment of an excimer lamp of the present invention.

The excimer lamp 1 is composed of a tubular discharge vessel 10 as a whole, a light emitting portion 11 filled with a gas for discharge, and a sealing portion for hermetically sealing the light emitting portion 11 at both ends thereof ( 12) is formed. The material of the discharge vessel 10 is made of a material, for example, synthetic quartz glass, which functions as a dielectric by dielectric barrier discharge and transmits vacuum ultraviolet light well.

The inside of the discharge vessel 10 is disposed so that the rod-shaped inner electrode 2 extends substantially at the center of the discharge vessel 10, and the outer surface of the discharge vessel 10 is disposed so that the outer electrode 3 closely adheres to it. . Both ends of the inner electrode 2 are bonded to the metal foil 13 at the sealing portion 12, and the outer lead 14 is bonded to the metal foil 13.

In the discharge space formed inside the light emitting portion 11, an excimer molecule is formed by a discharge (dielectric barrier discharge) via a dielectric material, and at the same time, a discharge gas such as xenon that radiates vacuum ultraviolet light from the excimer molecule Gas is sealed.

The inner electrode 2 is a rod-shaped electrode such as tungsten, and a coil-shaped elastic portion 21 is formed at an end thereof. An inner tube 22 made of a dielectric material is provided around the inner electrode 2 so that the inner electrode 2 is inserted into the inner tube 22. The inner tube 22 is made of, for example, synthetic quartz glass, and is covered on the outer surface of a portion that discharges between at least the outer electrode 3 of the inner electrode 2, and an end thereof is covered by the outer electrode ( It extends beyond the end of 3).

The inner electrode 2 and the inner tube 22 may be loosely in contact with each other through a small gap, or a larger gap may be formed. In addition, the coil-shaped elastic part 21 does not necessarily need to be provided in two places of the inner electrode 2, and should just be provided in at least one part.

In this embodiment, both ends of the inner tube 22 are open in the discharge space and do not exist at both ends of the inner electrode 2. Therefore, the inner electrode 2 is not directly covered by the inner tube 22 at both ends and is directly exposed to the gas for discharge.

The inner tube 22 is fixed to the inside of the discharge vessel 10 by the ring-shaped support member 30. The support member 30 is fitted to the inner tube 22 and fixed to the inner tube 22 by welding or adhesion.

The outer electrode 3 is an electrode in which metal wires are formed in a mesh shape, and is disposed to cover the outer surface of the discharge vessel 10. For this reason, the emission light from the discharge container 10 is transmitted through the mesh of the outer electrode 3 to be radiated. Moreover, when it is set as the structure which seamlessly woven one metal wire with respect to the outer electrode 3, adhesiveness with a discharge container increases and it is advantageous.

When the electric power feeding device (not shown) feeds the inner electrode 2 and the outer electrode 3, discharge is generated between the two electrodes via the discharge vessel 10 and the inner tube 22, which are dielectric materials, to generate a discharge. Excimer emission occurs in the dedicated gas.

Although the inner tube 22 is supported by the discharge vessel 10 by the supporting member 30, when the inner electrode 2 has sufficient self-holding rigidity, the supporting member 30 is required. Instead of this, the inner electrode 2 may be supported.

In this case, in order to prevent the inner tube 22 from moving in the longitudinal direction, the coil-shaped elastic portion 21 formed in the inner electrode 2 is used as a movement restricting member in the longitudinal direction of the inner tube 22. It can also function. In this case, the elastic part 21 is arrange | positioned adjacent to the edge part of the inner side pipe | tube 22, and it is set as the diameter larger than the inner diameter at least.

In the structure of the excimer lamp of this embodiment, since the dielectric is also covered by the inner electrode in the discharge space, the discharge between the outer electrode becomes stable, and a uniform state can be maintained, and unwanted arc discharge Generation of the excimer light is prevented, and the electrode is not burned and broken.                     

In addition, since the inner tube has a structure in which the end thereof is opened in the discharge space, thermal expansion in the longitudinal direction is not constrained at all, and thus is freely stretched. Therefore, a problem of damage and breakage based on the conventional structure joined at both ends of the discharge vessel is caused. Is resolved. In addition, the gas for discharge in the inner tube flows through the open end into the discharge space to suppress the temperature rise of the inner electrode and prevent its wear and tear, and at the same time, the temperature of the gas for discharge is averaged and the temperature. The increase can be suppressed and the fall of light output can be prevented.

In addition, since the inner electrode has an elastic portion, even if the inner electrode is thermally expanded, the thermal expansion component is absorbed by the elastic portion, and thus does not affect the sealing portion of the discharge vessel made of quartz glass having a different thermal expansion coefficient. Can be damaged.

2 shows a second embodiment of an excimer lamp according to the present invention.

The difference from the excimer lamp shown in FIG. 1 is that the inner electrode 2 is not a rod-shaped electrode but a coil-shaped electrode as a whole, and the outer electrode 3 is not a mesh-shaped electrode but a semi-cylindrical metal plate. It consists of.

The advantage that the inner electrode is coiled is that the weight is lighter than that of the rod-shaped electrode because it is made of a thin diameter metal wire. If the weight is light, it is advantageous in terms of vibration resistance and impact resistance. Moreover, since the electrode itself is an elastic body, there is no need to provide an elastic part separately as in the case of a rod-shaped electrode, and there is also an advantage that it can be manufactured at low cost.

The advantage that the outer electrode is a semi-cylindrical metal plate is that assembly workability is better than that of the mesh electrode. That is, in the case of the mesh-shaped electrode, work such as passing or winding through the discharge vessel is necessary, but in the case of the semi-cylindrical electrode, only the components molded in accordance with the outer diameter of the discharge vessel are inserted in advance. The task is complete. Moreover, when a metal plate has reflectivity with respect to an ultraviolet-ray, the light output of one direction can also be improved.

FIG. 3 shows an enlarged structure of the discharge vessel end portion of the excimer lamp shown in FIG. 1.

It is explanatory drawing for defining the area | region in which the inner electrode 2 is covered with the inner side pipe | tube 22, ie, the area | region which the inner electrode 2 exposes to a discharge space.

In the drawing, the distance D between the end of the outer electrode 3 and the end of the inner tube 22 should be at least greater than twice the discharge distance d. Not).

That is, when the relationship of D> 2d is not satisfied, there is a possibility that a strong discharge occurs at the exposed portion of the inner electrode 2 and the outer electrode 3, and this discharge is likely to become unstable discharge as described above. Because. In particular, in the case of alternating current lighting, discharge tends to be unbalanced every time the polarity is changed, since the relationship of polarity changes at the position of the dielectric.

Further, it is preferable to satisfy the relationship of D> 4d, and more preferably to satisfy the relationship of D> 6d.

4 shows the supporting member 30 of the inner electrode 2. (a) shows a bobbin-shaped support member, (b) shows a hollow support member in the middle using two discs, and (c) shows a plate-shaped support member.

The inner tube 22 is supported with respect to the discharge vessel 10 by the supporting member 30 attached to the inner tube 22 by welding, adhesion, or the like. The support member 30 can prevent the inner tube 22 itself from falling down due to gravity, as well as the inner tube 22 itself. 22) to prevent breakage and positional unevenness of discharge. In particular, when the discharge vessel 10 is elongated, this problem becomes remarkable. For example, when the length (the length of the discharge space) of the discharge vessel becomes 500 to 600 mm or more, the necessity of the supporting member becomes high.

The support member shown in (a) is a bobbin-shaped support member 30, fitted to the inner tube 22, and attached to the inner tube 22 by welding, adhesion or the like. And the recessed part 100 formed in the discharge container 10 fits in the recessed part on the circumference, and the inner side pipe 22 moves the inner side electrode 2 in the longitudinal direction by this. It regulates what to do.

Moreover, in the case of the two plate-shaped support members 30 shown to (b), the recessed part 100 is engaged between them.

In addition, in the case of the plate-shaped support member 30 shown to (c), two recessed parts 100 are formed in the both sides of this support member 30, and the longitudinal direction of the inner side pipe | tube 22 is carried out. Regulates movement.

Moreover, since these recessed parts 100 restrict | move the inner side pipe 22 in the longitudinal direction with respect to the discharge container 10, the fixing which loosely fixes the supporting member 30 with respect to the discharge container 10 is fixed. It functions as a means, and therefore it does not necessarily need to be formed in the whole outer periphery of the discharge container 10, and may be formed in one place or several places on a circumference.

And these recessed parts 100 can be made by dimple processing, for example.

In addition, although the structure of one end of the discharge container 10 is shown in FIG. 4, many support members 30 can also be provided in the center part or the other end of a discharge container.

In this case, the recessed part 100 does not need to be provided in all the support members 30, and it is possible to restrict the movement to the longitudinal direction of the inner side pipe | tube 22 by providing in at least one support member.

5 shows a third embodiment of the present invention. In this embodiment, in the first embodiment shown in FIG. 1, the support member 30 supports the inner tube 22 through which the rod-shaped inner electrode 2 penetrates against the discharge container 10. In contrast, the inner tube 22 is structured to be supported by the support 2a provided on the rod-shaped inner electrode 2.

FIG. 6 further shows the fourth embodiment, and in the second embodiment shown in FIG. 2, the coil-shaped electrode has a structure in which the coil-shaped inner electrode 2 is inserted to abut on the inner tube 22. The supporter 2b is provided in (2), and this coil-shaped electrode 2 is structured to be supported in the inner side pipe | tube 22. As shown in FIG.

7 shows a fifth embodiment. In the said Embodiments 1-4, although the inner electrode 2 showed the structure sealed at the both ends of the discharge container 10, it is not limited to this, The structure sealed only at one end may be sufficient.

In FIG. 7, the inner electrode 2 is sealed by a pinch seal or the like only at one end of the discharge vessel 10, in the drawing, at the right end 10a, and protrudes to the outside, and the left end 10b of the discharge vessel 10 is shown. Has a closed structure.

According to this embodiment, since the inner electrode 2 is sealed in the discharge container 10 only at one end, the influence on this discharge container 10 by thermal expansion can be further reduced.

In Embodiments 1 to 5, the inner tube 22 shows that both ends are open in the discharge space, but it is not necessary that both ends are open, and one end may be connected to the discharge vessel. This embodiment 6 is shown in FIG.

In FIG. 8, the left end 22a of the inner tube 2 is open in the discharge space, and the right end 22b is connected to the discharge container 10 by welding or the like.

Also in this Embodiment 6, since the left end 22a is open | released and free, the inner side pipe 22 is not restrained by the other member also about the thermal expansion of this inner side pipe 22, and it is distorted by the mounting location to the discharge container 10. This occurs and the stress does not concentrate.

Moreover, also in this Embodiment 6, as described in the said Embodiment 1, the support member 30 is attached to the inner side pipe 22, and the structure which supports the inner side pipe 22 with respect to the discharge container 10 is shown. However, in this embodiment, since the inner tube 22 is connected to the discharge container 10 at one end 22b, especially in the case of a small lamp, the support member 30 which supports the inner tube 22 is carried out. May be unnecessary.

In addition, about the support member 30 in each said Embodiment 1-6, as shown in FIG. 9, you may provide the notch part 31 in the light extraction direction (lower figure). The support member 30 is fixed to the inner tube 22 or the discharge vessel 10 by welding or the like.

By doing so, the problem that the discharge is not formed in the support member 30 or the light from the other light emitting portion is blocked and not radiated to the outside is solved. That is, in the structure in which the supporting member 30 is provided, since the supporting member 30 exists, there is no discharge space between the internal and external electrodes 2 and 3 in this portion, and no discharge is formed in this portion. Although the light in the oblique direction from the other light emitting part is blocked by the support member 30 and is not radiated to the outside of the discharge container 10, the cutout portion 31 discharges even under the support member 30. By forming a space, these problems can be solved.

The excimer lamp of the present invention is not limited to the structure shown in FIGS. 1 to 9. For example, the external electrode is not limited to a mesh electrode or a semi-cylindrical shape, and may be formed on the outer surface of the discharge vessel by printing or the like. As long as this outer electrode does not need to be physically constituted by one member, the outer electrode can be divided into a large number in the longitudinal direction of the discharge vessel and can be electrically connected. The advantage of this structure is that the long product can be easily manufactured and the light distribution can be adjusted.

The inner electrode is not limited to a rod-shaped electrode and a coil-shaped electrode, and may be anything as long as it has electrical characteristics in the inner tube and can be an electrode for excimer light emission. For example, a metal thin film is deposited on the inner surface of the inner tube. The advantage of this metal thin film is that the inner tube can be made small, and the metal thin film can be used as a reflecting mirror.

Moreover, an inner electrode can also be made tubular. In this case, adhesiveness with an inner side pipe | tube can also be improved by making C-shaped cross section which has a notch in a part in cross section.

When the inner electrode is formed of a coil, the coil is not formed from a single metal wire, but a structure in which a plurality of coils are connected to each other, a structure in which rod-shaped portions and coil portions are alternately arranged, or the pitch of the coil is in the longitudinal direction. It is possible to apply a structure that changes at. In particular, in the case where there is a deviation in the inner diameter and the thickness of the discharge vessel, it may be effective to eliminate the local nonuniformity of excimer light emission due to this deviation.

The structure of the sealing portion of the discharge vessel is not limited to a pinch seal, but may also be a thin seal, that is, a shrink seal structure, and a so-called single joint seal may be employed. However, the advantage of the joint seal is that the adhesion between the glass and the electrode is improved, and gas leakage and crack generation at the sealing portion can be more reliably prevented.

In addition, although the support member which supports an inner side pipe | tube was demonstrated as being attached to the said inner side pipe | tube by welding etc., it is not limited to this, It is set as the structure attached to the discharge container side, and an inner side pipe is loosely fitted to this support member, It may be supported. Even in this case, the inner tube can be freely thermally expanded and contracted without restraining thermal expansion in the longitudinal direction by the support member. However, since it is not preferable that the inner tube moves unnecessarily large in the longitudinal direction, fixing means for regulating the movement of the inner tube in the longitudinal direction of the inner electrode side or the like is separately provided as necessary.

As described above, the support member of the inner tube may be configured to be attached to either the discharge vessel or the inner tube.

You may arrange a getter in the discharge space. The getter is made of, for example, barium, zirconium and the like, and is effective because it can adsorb impurity gas. With regard to the arrangement of the getters, the dedicated getter housing chambers can be fixed by, for example, a structure provided at the end of the discharge vessel or by magnetic holding means.

In the structure shown in FIG. 1, when the numerical example is shown, the length (including the sealing part) of the discharge container 10 is 400 mm-1500 mm, for example, 1000 mm and the outer diameter of the discharge container 10 is phi 10 mm. It is -20 mm, for example, 15 mm. The length of the inner tube 22 is 200 mm to 1300 mm, for example, 800 mm, the outer diameter of the inner tube 22 is 4 mm to 8 mm, for example, 5 mm and the inner diameter is 2 mm to 6 mm. , 3 mm. The length of the inner electrode (rod-shaped electrode) is 300 mm to 1400 mm, for example, 900 mm, and the outer diameter is φ 1.5 mm to 5.9 mm, for example, 2.8 mm. The elastic part 21 has a length of 10 mm to 30 mm, for example, 20 mm, and an outer diameter of 2 mm to 7 mm, for example, 4 mm.

The width of the supporting member 30 is 3 mm to 7 mm, for example, 5 mm.

As the structure shown in FIG. 2, when the numerical example is shown about the part different from the structure shown in FIG. 1, the outer diameter of a coil-shaped inner electrode is φ1.5 mm-5.9 mm, for example, it is 2.8 mm.

As the structure shown in FIG. 3, with respect to the part different from the structure shown in FIGS. 1 and 2, the numerical example is shown. The discharge distance d is 2 mm to 7 mm, for example, 5.0 mm, and the distance D ) Is a numerical range larger than 2d, and is 4 mm to 14 mm, for example, 10 mm.

The excimer lamp has a discharge space through a dielectric between the outer electrode and the inner electrode, respectively. Although an excimer lamp is also called a dielectric barrier discharge lamp, it has the outstanding characteristic which does not exist in the conventional low pressure mercury lamp and the high pressure discharge lamp which strongly radiate the vacuum ultraviolet light of single wavelength.

Light of a single wavelength is determined by the encapsulation gas in the discharge vessel, light of wavelength 172nm in case of xenon gas (Xe), light of wavelength 175nm in case of argon gas (Ar) and chlorine gas (CL), Light of wavelength 191 nm for krypton (Kr) and iodine (I), light of wavelength 193 nm for argon (Ar) and fluorine (F); wavelength 207 for krypton (Kr) and bromine (Br) In the case of nm light, krypton (Kr) and chlorine (CL), light of wavelength 222 nm is emitted. Moreover, it also has the characteristic that it can flash and light at any time (within 1 second) as needed.

For excimer light emission, the voltage waveform supplied from the power feeding device to the excimer lamp is not limited to the sine wave, but may be a pulse waveform. In this case, it is preferable that the pulse waveforms at intervals (pause periods), rather than continuously supplying pulses, are light emitting efficiency, and the pulse waveforms are preferably applied as steep rise waveforms. This is because when a voltage of a steep rising waveform is applied, it is closer to a state in which a voltage is applied directly to the gas itself in the discharge vessel as compared with a case where a gentle voltage such as a sine wave voltage is applied. This is to avoid destroying the excimer molecule produced once. Further, for example, the numerical value of the rise is selected from the range of 0.03 μsec to 1 μsec, for example, 0.5 μsec, the pulse width is selected from the range of 0.5 μsec to 5 μsec, for example 1 μsec, and the rest period is 1 μm. It is selected from the range of second-100 microseconds, for example, 29 microseconds.

Fig. 10 shows a schematic configuration of an irradiation apparatus using an excimer lamp according to the present invention.

The excimer irradiation device 40 is formed in a box shape as a whole than the metal block 41.

Grooves are formed in the metal block 41, and excimer lamps 10 (10a, 10b, 10c) are disposed to fit the grooves. The metal block 41 is provided with through-holes 42 (42a, 42b) for cooling water through which cooling water flows, and sensors 43 (43a, 43b, 43c) for detecting the radiated light of the excimer lamp 1. The metal block 41 adopts aluminum, for example, from high heat transfer characteristics, ease of processing, and reflection characteristics with high vacuum ultraviolet light. In addition, although illustration is abbreviate | omitted, the temperature detection sensor with respect to a discharge container is arrange | positioned at the metal block 41. As shown in FIG.

The irradiation device 40 is provided with an introduction port 44a and an outlet port 44b for flowing an inert gas. The gas cylinder etc. are connected to the inlet port 44a through a valve, and the outlet port 44b is similarly connected to a vacuum pump through a valve. Although nitrogen gas is employ | adopted very generally as an inert gas, argon gas etc. can also be employ | adopted. In addition, the inert gas can be continuously flowed so as to be introduced from the inlet port 44a and discharged from the outlet port 44b before or after the treatment step.

The power feeding device 45 is disposed outside the irradiation device 40.

On the outside of the irradiation apparatus 40, the processing material W which receives the ultraviolet-ray radiated | emitted from the excimer lamp 10 is mounted on the processing bench 46. The treatment table 46 is made of, for example, stainless steel, and can heat the treated product W by providing a filament heater with a nichrome wire inside. Moreover, by providing the lifting mechanism which is not shown in figure in the processing stand 46, it is possible to make the process W approach the excimer lamp 1, and also to convey in a horizontal direction by providing a conveyance mechanism. It becomes possible.

Treatment gases such as oxygen gas, silane-based gas, hydrogen gas, argon gas, and the like are supplied to the treated product W, and the treatment gas and the emission light from the excimer lamp 1 can be treated. .

Moreover, the said irradiation apparatus is not provided with the permeable member which distinguishes both between a lamp and a process object. For this reason, the advantage is large in that the whole apparatus is downsized and an expensive ultraviolet transmission window member does not need to be used. Since the excimer lamp of the present invention is compact, it is possible to approximate the distance between the excimer irradiator 40 and the processing product W, so that the inert gas flows from the inlet port 44a to the outlet port 44b. The oxidation of the metal block 41 can be prevented.

However, the provision of a permeable member that distinguishes both between the lamp and the processed object is not excluded. By providing the permeable member, there is an advantage that the problem of floating matter from the processed matter adhering to the lamp or its vicinity can be solved.

In the excimer lamp of the present invention, since an inner tube made of a dielectric material is provided on the outer periphery of the inner electrode, two dielectrics are interposed between the inner electrode and the outer electrode, so that the discharge is stable and uniform in the discharge space. Is formed. In addition, since arc-like discharge is not generated regardless of the feeding polarity, the generation efficiency of the excimer light is high, and the electrode does not suffer from burning and breaking.

In addition, since the inner tube is open in the discharge space, the inner tube is freely stretched without restraining thermal expansion in the longitudinal direction, so that damage due to stress concentration or thermal distortion based on the structure bonded at both ends of the discharge vessel is prevented. · The problem of damage is solved.

Moreover, since the discharge gas in an inner side pipe | tube can distribute | circulate in a discharge space through the open end, the temperature rise of the inner side electrode covered by an inner side pipe | tube can be suppressed, the damage can be prevented, and the temperature in a discharge container is averaged. As a result, an increase in temperature of the gas for discharge can be suppressed, and a decrease in light output can be prevented.

Claims (7)

A discharge vessel made of a material which transmits ultraviolet rays and in which a gas for discharge is sealed, an inner electrode which extends the inside of the discharge vessel in a longitudinal direction and is hermetically sealed at the end of the discharge vessel, and an outer surface of the discharge vessel In the excimer lamp consisting of an outer electrode disposed in, The excimer lamp according to claim 1, wherein the inner surface of the inner electrode is covered with an inner tube made of a dielectric material, the outer surface of at least one of which discharges with the outer electrode at least at one end thereof in the discharge space. The excimer lamp of claim 1, wherein both ends of the inner tube are open in a discharge space. The excimer lamp according to claim 2, wherein the inner tube is supported by the discharge vessel by a supporting member. The excimer lamp according to claim 3, wherein the supporting member is attached to the inner tube, and the discharge vessel is provided with fixing means for restricting the movement of the supporting member in the longitudinal direction of the inner tube. . The excimer lamp according to claim 2, wherein the inner tube is supported by an inner electrode. The excimer lamp according to claim 1, wherein one end of the inner tube is opened in the discharge space and the other end is connected to the discharge vessel. The excimer lamp according to claim 1, wherein the inner electrode is sealed at both ends of the discharge vessel, and at least a portion thereof is formed with an elastic portion that is stretchable in the longitudinal direction.

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