JP2001185076A - Light source device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source which has a larger ejection area of excimer light to enlarge an emission area, has a stable discharge condition to stably and sufficiently work, and can not act as a high frequency noise source, without lowering of a luminance. SOLUTION: This excimer lamp 1 ionizes a raw material gas for creating excimer molecule using a grow-discharge to extract the excimer light emitted from the excimer molecule. The excimer lamp 1 includes a container 11 being filled with the raw material gas and having a light-transmissive window 15 of transmittance to natural radiation light, at least one cathode 13 being arranged in a straight-line shape within the container 11, and at least two electrode pairs having at least two anodes 14 being disposed within the container 11 to oppose with the cathode 13, wherein the light-transmissive window 15 is provided at an extending line X crossed to an imaginary plane defined by a parallel direction Y to the electrode pair.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a light source device,
More specifically, the present invention relates to a light source device that ionizes a raw material gas that generates excimer molecules by glow discharge and extracts spontaneous radiation emitted from the excimer molecules.

[0002]

2. Description of the Related Art In recent years, a light source device for generating ultraviolet light or vacuum ultraviolet light, such as an excimer laser, has been actively developed, and an excimer lamp such as an excimer lamp having a simpler structure than an excimer laser has been developed. Coherent light sources are also being developed. In this excimer lamp, a raw material gas for generating excimer molecules is sealed in a closed vessel such as a chamber or a valve, and natural radiation light (excimer light) from excited excimer molecules generated by discharging the raw material gas is used. ) To the outside.

[0003] Excimer lamps are broadly classified into non-electrode (external electrode) types in containers and electrodes with internal electrodes (internal electrodes) according to the form of discharge electrodes. As an electrode type, a type in which a pair of electrodes are disposed in the above-mentioned closed container (for example, see Japanese Patent Application Laid-Open No. 3-1463) is known. On the other hand, examples of the electrodeless type include a type using a dielectric barrier discharge that generates a high-frequency electric field in a discharge space. Furthermore, there is also a combination of the two. For example, an excimer lamp described in Japanese Patent Application Laid-Open No. 9-106783 is provided with a pair of internal electrodes for main discharge and external electrodes for dielectric barrier discharge.

[0004]

However, it is difficult for conventional electrode type excimer lamps to irradiate a sufficiently wide range or region with excimer light. In addition, in an excimer lamp using a dielectric barrier discharge, a stable discharge state does not always tend to be obtained, and thus the operation may be unstable. Further, since a high-frequency electric field is generated in the container, high-frequency noise, so-called E
MI (Electromagnetic Interference) may be caused. Moreover, a high voltage was always required to generate such a strong electric field. Under such circumstances, there has been a long-felt need for a light source device that has a wide excimer light irradiation area, can operate sufficiently stably, and does not become a noise source.

In view of the foregoing, the present invention has been made in view of such a conventional problem, and the emission area of the excimer light is enlarged without increasing the luminous intensity and the illuminance of the irradiation area of the excimer light. It is an object of the present invention to provide a light source device capable of expanding a region, stabilizing a discharge state and performing sufficiently stable operation, and not being a high-frequency noise source that causes EMI.

[0006]

Means for Solving the Problems The present inventors have intensively studied to solve the above-mentioned problems, and in the conventional electrode type excimer lamp, even if the input current is increased to increase the discharge current, the discharge current is not increased. Since a corresponding excimer light output cannot be obtained, it has been found that it is difficult to illuminate a wide area without lowering the illuminance of the irradiation area. Based on this finding, the present inventors have conducted further studies, and as a result, arrived at a member configuration and structure of a light source device which is extremely effective in solving the conventional problems, and completed the present invention.

That is, the light source device according to the present invention ionizes a source gas for generating excimer molecules by glow discharge and extracts spontaneous radiation emitted from the excimer molecules, and the source gas is sealed. And a sealing body provided with a light emitting portion having a property of transmitting natural radiation light, and at least two pairs of electrodes arranged inside the sealing body.

[0008] In the light source device configured as described above, the raw material gas atoms sealed in the envelope are converted into dimer photons by discharge to generate excimer molecules, and spontaneous emission light is generated by the electron transition of the excimer molecules. Is released. At this time, since the discharge mode is a glow discharge, the voltage fluctuation with respect to the change of the discharge current is small, and a decrease in the electrode applied voltage (hereinafter, referred to as “sustain voltage”) maintained during the discharge is suppressed. When the sustaining voltage is maintained at a sufficiently high level, the abundance ratio of excimer molecules excited to a high energy level increases, so that the luminous efficiency of excimer light of a relatively short wavelength (ultraviolet light or vacuum ultraviolet light) is obtained. Is enhanced.

Further, since the excimer molecules at such a high energy level are widely and dilutely distributed, the concentration of glow discharge (discharge density) is appropriately reduced, and the discharge path is widened. The emission region of the excimer light is enlarged. As a result, the emission intensity of the excimer light in the enclosure is increased, and there is no possibility that the luminous intensity of the light source device is reduced. And
Since glow discharge for obtaining excimer light with high emission intensity is performed in at least two provided electrode pairs,
The emission region of the excimer light is enlarged, and the area (exit area) from which the excimer light is emitted can be increased. Therefore,
It is possible to irradiate a wider area with excimer light with the same illuminance as before.

In addition, according to various conditions such as the shape of the sealing body, the type of the raw material gas, the internal pressure of the raw material gas, and the like, the distance between the electrodes constituting the electrode pair (electrode distance) and the arrangement distance between the electrode pairs. By appropriately adjusting the above, it is possible to avoid the concentration of the discharge and to surely separate the discharge path to stably perform the glow discharge. Therefore, output fluctuation of excimer light as seen in a conventional excimer lamp using a dielectric barrier discharge is sufficiently prevented, and the operation of the photoelectric device can be stabilized. Furthermore, since it is not necessary to generate a high-intensity high-frequency electric field inside the envelope, there is no possibility that the light source device becomes a noise source for peripheral devices.

In addition, the light source device of the present invention employs electrode discharge, and does not require a high voltage which is always required to generate a high-intensity high-frequency electric field. Therefore, compared to the conventional excimer lamp using the dielectric barrier discharge, it is possible to reduce the operating voltage and to reduce the scale of the power supply. In addition, since the number of electrode pairs can be appropriately selected, there is an advantage that the sealing body and thus the light source device can be easily formed into a desired shape. Further, since the amount of heat generated in the glow discharge is smaller than that in the arc discharge, for example, the temperature rise of the light source device can be suppressed, and the light source device can be installed in a vacuum atmosphere. Therefore, it becomes very useful as a light source device that outputs vacuum ultraviolet light.

The electrode pair includes at least one cathode linearly arranged inside the envelope and at least two anodes arranged inside the envelope so as to face the cathode. It is preferable that the light emitting portion is provided on an extension line intersecting a virtual plane determined in the parallel direction of the electrode pair, and it is preferable that the intersection angle between the virtual plane and the extension line is larger, and that the light emitting portion is Is preferably provided on an extension line orthogonal to an imaginary plane determined by the parallel direction.

[0013] In the light source device having such a configuration, at least one cathode is linearly arranged inside the envelope,
At least two anodes are arranged inside the envelope so as to face the cathodes, and at least two electrode pairs are configured by the cathodes and the anodes. An imaginary axis connecting the tips of the anodes) is located on the same plane. Therefore, the light emitting region of the excimer light due to the glow discharge is aligned on this plane, that is, in the direction in which the electrode pairs are arranged in parallel, so that a large-area surface light source is formed on the same plane. Since the light emitting portion is provided on an extension line intersecting this plane (virtual plane) determined by the parallel direction of the electrode pairs, excimer light having a large light beam cross section is emitted from the light emitting portion. In particular, when the light emitting portion is provided on an extension line orthogonal to the virtual plane, the light beam cross section of the excimer light tends to be the largest. Accordingly, since the emission area of the excimer light is significantly increased as compared with the conventional case, it is possible to irradiate a wider area with the same illuminance as the conventional case.

A power supply for applying a voltage to each electrode pair;
It is preferable that a resistance circuit be connected between the power supply and at least one of the anode and the cathode, and limit a current flowing through the electrode pair during glow discharge. Further, it is preferable that a diode that is connected between the power supply and the anode and limits a current flowing through the electrode pair when glow discharge is performed is provided.

With this configuration, the discharge current can be limited to a range in which the glow discharge is stably maintained. In addition, when the power supply voltage is constant, a desired discharge current can be easily obtained according to the shape of the envelope and the electrode conditions by changing the resistance value of the resistance circuit. On the other hand, when a diode is used, the backflow of current can be sufficiently suppressed. As described above, both the resistor circuit and the diode function as good discharge current limiting means, and it is possible to more stably maintain the glow discharge by each electrode pair.

Further, it is more preferable that the power supply is a DC power supply for applying a pulse voltage to the electrode pair. Excimer lamps using a conventional dielectric barrier discharge require the use of an AC power supply to apply a high-frequency electric field to the source gas of excimer molecules, whereas the light source device of the present invention uses a DC power supply and Any of the AC power supplies may be used.
When a DC power supply is used, when the voltage is pulsed, that is, when the voltage is applied in a pulse operation, the excimer light emission efficiency and the excimer light peak output (peak power) are increased as compared with continuous operation. Can be This is because the generation and disappearance of excimer molecules is proportional to the number of pulses.
The number of times leads to an increase in output.

Furthermore, it is more preferable that a reflecting portion for reflecting spontaneously emitted light (excimer light) is provided at a position inside the envelope facing the light emitting portion. With such a configuration, a part of the excimer light generated in the enclosure is reflected by the reflection part and emitted from the light emission part to the outside of the enclosure, so that the excimer light output of the light source device can be increased. Becomes The shape of the reflecting portion may be flat or curved.

Further, the source gas contains at least one kind of rare gas, rare gas halide and nitrogen gas, and at least one kind of gas among hydrogen isotope gas, halogen gas and mercury vapor. It is more preferable that the mixed gas is composed of: When the source gas is a mixed gas containing such gas components, it becomes possible to extract various excimer lights having different emission spectrum shapes depending on the types, mixing ratios, partial pressures, and the like of the gas components. Therefore, a light source device that outputs excimer light according to various uses can be obtained.

Further, it is desirable that the cathode has a projection formed at a portion facing the anode. In this case, since the location of the discharge is defined by the convex portion formed on the cathode, the independent glow discharge by the electrode pair can be easily separated without fail. This is particularly effective when the number of cathodes is smaller than the number of anodes, and one cathode is a common cathode (common electrode) shared by a plurality of anodes. In this case, the shape of the tip of the projection may be flat, may have a projection, or may be projection.

Further, it is more preferable that the cathode and / or the anode have a metal compound layer provided on the surface.
When the source gas contains corrosive gas such as halogen gas,
Corrosion of the electrode due to halogenation of the metal atom of the electrode conductor part progresses, and there is a possibility that the life of the electrode is shortened or discharge characteristics are deteriorated. Therefore, by providing a metal compound layer on the surface of such a metal, a corrosive gas such as a halogen gas is blocked by the metal compound layer, and the corrosion of the electrode is suppressed. It is preferable that the metal compound layer be made of a compound having excellent corrosion resistance to halogen gas. In addition, when such a metal compound layer is provided on the surface of the cathode, the work function of the cathode is reduced, and the electron emission characteristics of the cathode can be improved.

At least one of the electrode pairs has a smaller electrode interval and a larger resistance value of the connected resistance circuit than other electrode pairs different from the other electrode pairs. Is more preferable. In the light source device configured as described above, the electrode pair whose electrode interval is narrower than the others starts at a lower applied voltage than the other electrode pairs (starts glow discharge). In this case, the periphery of the electrode pair is ionized by glow discharge, and the startability of another electrode pair near the electrode pair is enhanced. As a result, the starting voltage of the other electrodes is also reduced, and the startability of the light source device can be improved.

[0022] In addition, it is more preferable that a partition is provided between the electrode pairs in the parallel direction of the electrode pairs and separates the electrode pairs from each other. With this configuration, the partition wall effectively prevents the discharge occurring at one electrode pair from flowing to another electrode pair. Therefore, it is possible to further stabilize the glow discharge. At this time, since the partition is disposed between the electrode pairs in the parallel direction of the electrode pair, if the partition is installed so as to be substantially orthogonal to the parallel direction of the electrode pair,
Excimer light emitted by the glow discharge of each electrode pair can be emitted from the light emitting portion to the outside without being blocked by the partition. Therefore, there is almost no possibility that the emission area of the excimer light is reduced, and there is almost no possibility that a shadow is generated in the irradiated area.

[0023]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Note that the same components are denoted by the same reference numerals, and redundant description will be omitted. Also,
The vertical and horizontal relationship is based on the vertical and horizontal relationship in the drawings unless otherwise specified.

FIG. 1 is a perspective view schematically showing the structure of a first embodiment of the light source device according to the present invention. The excimer lamp 1 as a light source device has a substantially cylindrical shape, and three cathodes 13 are provided linearly through the upper wall 12a of a hollow gas-filled container 11 (sealing body). Thus, three anodes 14 are provided so as to penetrate the bottom wall 12b. Thus, the cathode 13 is disposed vertically above the anode 14. These cathode 13 and anode 14 are
The cathode 13 and the anode 14 which are arranged inside the gas sealing container 11 and face up and down form three pairs of electrodes.

In each electrode pair, the cathode 13 and the anode 14 are preferably formed by the following formula (1): Sc> Sa (1) [where Sc is the surface 13S of the cathode 13 facing the anode 14]
Sa represents the area of the surface 14S of the anode 14 facing the cathode 13. ] Are set so as to satisfy the relationship shown in [1].

Further, the surfaces of the conductor portions of the cathode 13 and the anode 14 are covered with a metal compound layer. In addition, a light transmitting window 15 (light emitting portion) having a property of transmitting excimer light, which will be described later, is provided on a side wall of the gas sealing container 11. The light transmission window 15 is provided on an extension line X that intersects a virtual plane defined by the parallel direction Y of the electrode pairs. That is, the angles θ ≠ 0 ° and θ ≠ 180 °.

Further, in the internal space of the gas filled container 11,
A source gas for generating excimer molecules is sealed so as to have a predetermined internal pressure, and a predetermined voltage is applied to each electrode pair in this state. The top wall 12a and the bottom wall 12b of the gas sealing container 11 are formed of an insulating member, and are generally called a base.
The side wall of the gas sealing container 11 is formed of a member such as metal or quartz. Further, the light transmission window 15
Is formed of, for example, quartz, magnesium fluoride, calcium fluoride, or the like.

In the excimer lamp 1 configured as described above, when a predetermined voltage is applied to the electrode pairs, discharge starts in each electrode pair. Current flowing through the electrode pair (discharge current)
As the current increases, the form of discharge shifts to glow discharge (developing into normal, abnormal, abnormal glow discharge with the increase in current) through Townsend discharge, and to arc discharge when the current further increases. And migrate. In the excimer lamp 1 of the present invention, the voltage applied to each pair of electrodes is adjusted so that the discharge current is such that the glow discharge is maintained.

At this time, inside the gas filled container 11,
The source gas atoms are converted to dimer photons to produce excimer molecules in an excited state.
Spontaneous emission light (excimer light) having a continuous spectrum is emitted. And some excimer light L (natural radiation light)
Are emitted to the outside of the gas filled container 11 through the light transmission window 15.

As described above, since the excimer lamp 1 operates by the glow discharge, the voltage fluctuation with respect to the change of the discharge current is small, the decrease in the sustain voltage is suppressed, and the low voltage characteristics are favorably maintained. In this case, the voltage is maintained at a sufficiently high level, and the abundance ratio of excimer molecules excited to a high energy level increases, so that the excimer light mainly composed of relatively short wavelength ultraviolet light or vacuum ultraviolet light is used. Luminous efficiency is increased. Further, excimer molecules in such a high energy level are widely and dilutely distributed, so that the concentration (discharge density) of glow discharge is appropriately reduced and the discharge path is widened. Therefore, the emission region of the excimer light is expanded,
In addition, as described above, the emission efficiency of excimer light is also increased, so that the emission intensity of ultraviolet light or vacuum ultraviolet light as excimer light is increased. Therefore, excimer light having a sufficient output can be obtained from the excimer lamp 1.

Since the glow discharge for obtaining the excimer light having a high emission intensity is performed by the electrode pair provided with at least two electrodes, the excimer light emission region is enlarged and the emission area of the excimer light is reduced. It is made larger than that. As a result, a decrease in the luminous intensity of the excimer lamp 1 is prevented, and a wider area can be irradiated with the excimer light with the same illuminance as the conventional one.

Further, since the cathodes 13 are arranged linearly and the anodes 14 are arranged at positions facing these cathodes, the electrode pairs are arranged along the parallel direction Y, and their electrode opposing axes are aligned. They are located on the same plane. Therefore, the discharge path of the glow discharge formed along the electrode facing axis appears on this plane, and the light emitting region of the excimer light is aligned in the parallel direction Y of the electrode pairs. At this time, a large-area surface light source is formed on a virtual plane (same plane) determined by the parallel direction Y. Since the light emitting portion is provided on the extension line X intersecting the virtual plane, excimer light having a large light beam cross section is emitted from the light emitting portion.

In particular, when the light emitting portion is provided on an extension line perpendicular to the virtual plane, that is, when θ = 90 °, the cross section of the light beam of the excimer light becomes maximum. Therefore, the emission area of the excimer light is significantly increased as compared with the conventional case, and it is possible to irradiate a wider area with the same illuminance as the conventional case. Moreover, since the ratio of the ultraviolet light and the vacuum ultraviolet light in the excimer light is increased as described above, it is possible to obtain a light source device in which the irradiation area by the ultraviolet light and the vacuum ultraviolet light from the light source device is particularly improved. .

Further, an electrode gap G1 between the cathode 13 and the anode 14, an arrangement gap G2 between the electrode pairs, and the like are determined according to various conditions such as the shape of the gas sealing container 11, the type of the source gas, and the internal pressure of the source gas. Is appropriately adjusted, the discharge is prevented from being concentrated, the discharge is reliably separated, and an independent glow discharge is stably performed by each electrode pair. When the glow discharge is stably maintained in this manner, the output fluctuation of the excimer light, which has been conventionally seen, can be sufficiently prevented, and the operation of the excimer lamp 1 can be stabilized. Further, since it is not necessary to generate a high-intensity high-frequency electric field inside the gas enclosure 11, there is no possibility that the excimer lamp 1 becomes an electromagnetic noise source that exerts electromagnetic adverse effects (EMI) on peripheral devices. In addition, the excimer lamp 1 uses an electroded discharge, and does not require a high pressure that is always needed to generate a high-intensity high-frequency electric field.
Therefore, the operating voltage is suppressed lower than that of an excimer lamp using a conventional dielectric barrier discharge, and the scale of the power supply device used for the excimer lamp 1 can be reduced.

Further, by arranging the cathode 13 vertically above the anode 14, the following operation and effect can be obtained satisfactorily. When the cathode 13 is provided below the anode 14, electrons generated by ionization due to discharge move upward from below, and the moving speed of the electrons is:
It is slower than when the cathode 13 is above. At this time, if the gap length between the electrodes is not sufficiently short, the deflection of the electron path due to the electric field of positive ions (radicals) generated by ionization increases. The mass difference between an electron and a positive ion is very large, and in the same electric field, the moving speed of the electron is much higher than that of the positive ion. Therefore, the discharge path is excessively expanded due to the deflection of the electron path, and it tends to be difficult to stably maintain the glow discharge.

On the other hand, if the cathode 13 and the anode 14 are horizontally opposed at the same height, the electron mass is considerably smaller than the mass of the positive ions, so that the electrons are affected by thermal diffusion. While positive ions are more likely to convection upward, positive ions are more likely to convection downward. Therefore, the glow discharge tends to be unevenly distributed so as to wrap around the electrode. In the excimer lamp 1, the cathode 13 is disposed vertically above the anode 14, so that the glow discharge can be stabilized and the glow discharge can be prevented from being unevenly distributed. As a result, it is possible to stably extract high-output excimer light.

By the way, even if the cathode 13 is disposed vertically above the anode 14, there is no danger that the discharge path will be excessively widened. However, if the relationship represented by the above equation (1) is satisfied, , The area Sc of the cathode 13 is
Is larger than the area Sa of the anode 14
The positive ions tend to be easily converged on the surface 13S of the cathode 13 on the surface 14S. Therefore, the fluctuation of the discharge current is suppressed, the glow discharge becomes more stable, and the output of excimer light can be further stabilized. Further, the glow discharge has a smaller discharge current than the arc discharge, and the temperature rise of the anode 14 due to the anode loss is extremely small. Therefore, even if the area Sa of the anode 14 is smaller than the area Sc of the cathode 13, the discharge is not generated. It has the advantage of being stable.

On the other hand, in the glow discharge, the work function of the cathode 13 and the anode 14 is larger than that of the arc discharge, and electrons are less likely to be emitted from the surface of the cathode 13, so that the amount of emitted electrons per unit area of the cathode 13 is small. Therefore, a discharge may be generated from the back surface of the electrode or the support of the electrode, and the discharge may be unstable. On the other hand, in the excimer lamp 1, since the area Sc of the cathode 13 is larger than the area Sa of the anode 14, a discharge easily occurs between the surface 13S of the cathode 13 and the surface 14S of the anode 14. Accordingly, the operation of the glow discharge becomes sufficiently stable, and the output fluctuation of the excimer light can be sufficiently suppressed.

Here, the source gas for producing excimer molecules is helium, neon, argon, krypton,
Noble gases such as xenon, rare gas halides such as argon fluoride, krypton fluoride, xenon chloride and xenon fluoride, nitrogen gas which is an inert gas, hydrogen isotope gas (H ₂ , D ₂ , T ₂ , HD, HT, DT; wherein H represents hydrogen, D represents deuterium, and T represents tritium.), Halogen gas such as fluorine, chlorine, bromine, or mercury vapor; Or a mixture of two or more.

In particular, a mixed gas containing at least one of a rare gas, a rare gas halide and a nitrogen gas and at least one of a hydrogen isotope gas, a halogen gas and mercury vapor is used as a source gas. It is suitable to use as. When the source gas is a mixed gas composed of such gas components, it becomes possible to extract various excimer lights having different emission spectrum shapes depending on the types, mixing ratios, partial pressures and the like of the gas components. Therefore, the excimer lamp 1 that outputs excimer light according to various uses can be obtained.

When xenon gas is used as a source gas, the internal pressure is preferably 20 to 100 kPa,
More preferably, the pressure is 25 to 70 kPa.
When the internal pressure of the source gas in the gas enclosure 11 is extremely low, the concentration of the source gas atoms becomes extremely low, and the interatomic force acting between the atoms is too weak to cause sufficient dimerization, Excimer molecules are not easily formed. Since the excitation level of such an atom is quantized and discontinuous, the emission spectrum becomes a bright line spectrum.

On the other hand, when the internal pressure of the raw material gas is increased, dimerization occurs due to the action of the atomic force, and excimer molecules are generated. Since the excitation level of the excimer molecule changes continuously between the atomic excitation potential at the point at infinity and the bonding potential of two atoms, the emission spectrum of the excimer molecule is a continuous spectrum. The peak wavelength in the continuous spectrum fluctuates due to the internal pressure of the source gas and the like, for example,
As the internal pressure decreases, the peak wavelength shifts to shorter wavelengths.

In the excimer lamp 1, if the internal pressure of the xenon gas (source gas) is less than 20 kPa, the peak wavelength tends to shift to a shorter wavelength side than the ultraviolet region, but the atomic concentration is reduced. As a result, the decrease in the amount of excimer molecules produced becomes remarkable, and excimer light having a sufficient emission intensity cannot be obtained. Also, the atomic concentration decreases,
The effect of restricting the discharge path by atoms is not effectively exerted, and it tends to be difficult to obtain a stable glow discharge. On the other hand, if the internal pressure is less than 20 kPa, the excimer light output with respect to the input power, that is, the conversion efficiency tends to be not sufficiently increased.

On the other hand, it is preferable to increase the internal pressure of the source gas since the upper limit of the discharge current at which a stable glow discharge can be performed gradually increases. This is presumed to be because the increase in the concentration of the raw material gas makes it difficult for the temperature of the cathode 13 to rise even when the discharge current increases, and the threshold value of the discharge current at which thermionic emission occurs shifts to the high current side. Is done. In addition, as the internal pressure increases, the sustain voltage due to the increase in the discharge current is less likely to decrease, and the normal glow discharge tends to be favorably maintained. From these viewpoints, it is determined that the higher the internal pressure of the source gas, the more preferable.

On the other hand, when the internal pressure of the xenon gas (source gas) exceeds 100 kPa, the working distance of the interatomic force is extremely narrowed, and the dimerization of atoms at a low excitation potential becomes remarkable. Tend to shift toward the visible or infrared region. As a result, the emission intensity of ultraviolet light or vacuum ultraviolet light may be reduced. In addition, since the atomic density of the source gas increases, the discharge path is narrowed, and the emission region of excimer light tends to be reduced.
Further, when the internal pressure exceeds 100 kPa, the conversion efficiency from input power to excimer light is significantly reduced.
In addition, from the viewpoint of maintaining high conversion efficiency, it is more preferable that the internal pressure of the source gas is 25 to 70 kPa.

Further, since the metal compound layer is provided on the conductor surfaces of the cathode 13 and the anode 14, even if the source gas contains a corrosive gas such as a halogen gas, the halogen gas is blocked by the metal compound layer. In addition, the contact between the metal atoms of the conductor and the halogen atoms is sufficiently suppressed. Therefore, it is possible to sufficiently prevent the life from being shortened due to the corrosion of the electrode and to sufficiently prevent the deterioration of the discharge characteristics. Further, when such a metal compound layer is provided on the surface of the cathode 13, the work function of the cathode 13 is reduced, and the electron emission characteristics of the cathode 13 can be improved.

Here, the material for forming the cathode 13 is not particularly limited, but for example, a metal such as molybdenum, iron, nickel, cobalt, copper, tungsten, aluminum, manganese, chromium, platinum, gold, etc. , Or carbon, and alloys thereof may be used.
The material for forming the anode 14 can also include the above metals, their alloys, and carbon. As a material of the metal compound layer covering the surface of the cathode 13 and / or the anode 14 formed of these materials, a material having excellent corrosion resistance to corrosive gas is preferable.
Metal oxide, for example, yttrium oxide (Y ₂ O ₃ ) and the like can be given.

FIG. 2 is a perspective view schematically showing the structure of a light source device according to a second embodiment of the present invention. The excimer lamp 2 shown in FIG. 2 is provided with a reflecting portion 21 capable of reflecting excimer light on the inner surface of the gas sealing container 11 facing the light transmitting window 15. Is the same as the excimer lamp 1 shown in FIG. According to the excimer lamp 2 configured as described above, a part of the excimer light generated inside the gas sealing container 11 is reflected by the reflection part 21 and emitted from the light transmission window 15 to the outside of the gas sealing container 11. You. Therefore, the output of excimer light can be further increased as compared with the excimer lamp 1 shown in FIG.

The reflecting portion 21 is provided along the inner peripheral wall of the gas-filled container 11 having a hollow cylindrical shape, and has a curved inner surface, so that the reflected excimer light is transmitted to the light transmitting window 15. The efficiency of light collection (light collection efficiency) is improved as compared with, for example, a case where the reflection portion is a flat surface. Therefore, it is possible to increase the intensity at the center of the excimer light beam while maintaining the emission area, and it is possible to improve the output of the excimer lamp 2.

FIG. 3 is a perspective view schematically showing the structure of a third embodiment of the light source device according to the present invention. The excimer lamp 3 shown in FIG. 3 includes an optical lens 31 having a property of transmitting excimer light instead of the light transmission window 15. As the optical lens 31, various lenses such as a convex lens, a concave lens, a cylindrical lens, and a fly-eye lens can be used alone or in combination depending on the application, and the optical conditions such as the shape and the focal length are also used. Can be selected according to

In such an excimer lamp 3,
Excimer light generated inside the gas enclosure 11 and reaching the optical lens 31 is condensed or scattered by the optical lens 31 and emitted to the outside. Therefore, the irradiation area of the excimer light L output from the excimer lamp 3 can be arbitrarily changed according to the purpose and use. For focusing,
The energy density of the excimer light L in the condensing part is extremely increased. On the other hand, in the case of diffused light, it is possible to irradiate a wider area.

FIG. 4 is a perspective view schematically showing the structure of a light source device according to a fourth embodiment of the present invention. FIG. 4 (a) is an overall view of the light source device, and FIG. 4 (b) is a light source. FIG. 3 is a perspective view showing a cathode used in the device. In addition, FIG.
It is a figure which shows the state which looked at the cathode shown in FIG. 4 (a) upside down. As shown in FIG. 4A, the excimer lamp 4 is
One flat cathode 43 is disposed inside the gas enclosure 11 and vertically above three anodes 14 so as to face each other. Thus, in the excimer lamp 4, one cathode 43 and three anodes 14 constitute three electrode pairs.

As shown in FIG. 4 (b), on the surface 43S of the flat plate portion of the cathode 43 facing the anode 14, a protruding projection 43a is located at a position substantially facing the respective anodes 14 in the vertical direction. There are a total of three locations. Furthermore, the surface 43 of the cathode 43
Assuming that the area of S is Sc 'and the total area of the surface 14S of the anode 14 is Sa', the following formula (2) is preferably provided between Sc 'and Sa': Sc '>Sa' ... ( The relationship shown in 2) holds.

In the excimer lamp 4 having such a configuration,
The cathode 43 is a common electrode that also serves as a counter electrode for the plurality of anodes 14. Further, the cathode 43 has a flat plate shape,
In comparison with the case where the same number of cathodes are provided as the number of anodes, the electrode interval between the cathode 43 and the anode 14 can be easily set to a constant distance. Therefore, deviation from the set value of the electrode interval hardly occurs, and it is possible to sufficiently prevent the discharge from being concentrated on a certain electrode pair. Therefore, the discharge path of the glow discharge by each electrode pair is ensured in a separated state. As a result, a decrease in the luminous efficiency of the excimer light can be effectively suppressed.

Further, since the number of cathodes to be installed is reduced, the work of installing the cathodes is simplified, and the configuration of the excimer lamp 4 is also simplified, so that the productivity of the excimer lamps 4 is increased. In particular, in the excimer lamp 4, the trouble of arranging a plurality of cathodes on a straight line can be omitted. In addition, since there is no displacement of the cathode 43 in the parallel direction Y, it is possible to further enhance the stability of the glow discharge.

Further, the surface 43S of the flat plate portion of the cathode 43 becomes a substantial cathode, and its area Sc 'is determined by the individual area (Sa) of the surface 14S of the anode 14 facing the cathode 43, and furthermore, the total value thereof. It becomes easier to make it larger than Sa '. Therefore, the relationship shown in the above equation (2) is easily achieved, so that
The stability of glow discharge is further enhanced. Furthermore, since the same number of protrusions 43a as the number of the anodes 14 are formed on the surface 43S of the cathode 43, three electrode pairs are clearly defined, and discharge locations (three discharge paths) are defined. Therefore, the discharge paths can be more reliably separated. Moreover, the convex portion 4
3a is almost vertically opposed to each anode 14,
The discharge path is more reliably separated. Therefore, it is possible to sufficiently prevent the emission efficiency of the excimer light from decreasing.

FIG. 5 is a perspective view schematically showing the structure of a fifth embodiment of the light source device according to the present invention. The excimer lamp 5 shown in FIG. 5 is provided with the above-described reflecting portion 21 constituting the excimer lamp 2 shown in FIG. 2 at the same position on the inner surface of the gas sealing container 11 of the excimer lamp 4 shown in FIG. The excimer lamp 2 has high output characteristics and high excimer lamp 4 characteristics such as high stability and high productivity.

FIG. 6 is a perspective view schematically showing the structure of a light source device according to a sixth embodiment of the present invention. The excimer lamp 6 (light source device) shown in FIG. 6 is an optical lens 31 constituting the above-described excimer lamp 3 shown in FIG. 3 instead of the light transmission window 15 of the excimer lamp 4 shown in FIG.
The excimer lamp 3 is provided with the same characteristics as those of the excimer lamp 3, such as a condensing characteristic or a scattering characteristic of the excimer light L,
The excimer lamp 4 has both high stability and high productivity, which are characteristics of the excimer lamp 4.

FIG. 7 is a schematic configuration diagram showing the configuration of a seventh embodiment of the light source device according to the present invention. An excimer light source device 10 (light source device) shown in FIG. 7 includes the above-described excimer lamp 1 as a component, and a DC power supply HV1 is applied to each electrode pair including a cathode 13 and an anode 14 of the excimer lamp 1. (Power supplies) are connected to each other. A limiting resistor R1, a correction resistor R2, and a diode D1 are connected between the DC power supply HV1 and the anode 14 in this order from the anode 14 side. Thus, the limiting resistor R1
And the correction resistor R2 constitute a resistor circuit. The circuits including the respective electrode pairs include start switches SW1, S
The starting circuit 7 is connected to W2 via wiring.

Excimer light source device 1 configured as described above
0, the start switches SW1 and SW2 are closed for a predetermined pair of electrodes while a DC voltage is applied from the DC power supply HV1 to the pair of electrodes, and a start signal from the start circuit 7 (for example, an open voltage or more). The discharge is started by trigger voltage, application of high frequency electric field or magnetic field). Once the discharge is started, the voltage applied by the DC power supply HV1, the resistance of the diode D1, the resistance of the limiting resistor R1, the resistance of the correction resistor R2, the structure or shape of the excimer lamp 1, the cathode 13 and the anode 14 Between the electrodes, the area of the cathode 13, the anode 1
A discharge current determined by the area 4, the type of the source gas, the internal pressure of the source gas, and the like flows, and the glow discharge is maintained.

In the excimer light source device 10, the above conditions are set so that the discharge current is such that the glow discharge can be stably maintained. At this time, the discharge current flowing between the electrodes is on the order of mA, and the discharge current can be stably obtained by the DC power supply HV1 having a maximum voltage of about several hundred volts and the resistor circuit. In other words, by using the resistor circuit, the discharge current can be limited to a good range in which the glow discharge is stably maintained. on the other hand,
The diode D1 prevents a backflow of current, and thereby functions as a discharge current limiting unit. Therefore, by providing these current limiting means, it becomes possible to maintain the glow discharge more stably,
Independent glow discharge paths can be reliably separated for each electrode pair.

Here, the DC power supply HV1 may be a constant voltage power supply or a constant current power supply. When a constant voltage power supply is used, a voltage change due to a voltage drop during discharging is compensated, and a current change at that time can be corrected by the correction resistor R2. On the other hand, when using a constant current power supply,
The voltage fluctuation is compensated by the correction resistor R2.

As described above, the discharge current is determined by affecting a plurality of conditions mutually and in a complicated manner. When xenon gas is used as a raw material gas, the following discharge current is determined. This is preferable. That is, the internal pressure of the xenon gas is preferably 20 to 100.
kPa, more preferably 25 to 70 kPa, when the discharge current is preferably 1 to 15 mA per discharge, more preferably 1 to 10 mA, excimer light tends to be obtained with high output and high conversion efficiency. It is in. When the discharge current is in such a range, the output of the excimer light increases almost linearly with an increase in the discharge current, and the sustain voltage during this time is maintained at a substantially constant value. Therefore, it is considered that the constant voltage characteristics are realized and the normal glow discharge is favorably maintained.

If the discharge current is less than 1 mA, the output of excimer light tends not to be sufficiently increased. on the other hand,
When the discharge current exceeds 15 mA, the drop in the sustain voltage becomes remarkable, and the discharge tends to shift to arc discharge through abnormal glow discharge. As a result, the output of the excimer light becomes saturated, and there is a possibility that the conversion efficiency of the excimer light into excimer light is significantly reduced. In addition, the DC power supply HV1
Is preferably 150 V or more. At this time, it is preferable that the resistance value of the resistance circuit including the limiting resistor R1 and the correction resistor R2 is 1 kΩ or more. If the maximum value of the DC voltage is less than 150 V and the resistance value of the resistor circuit is less than 1 kΩ, it tends to be difficult to stably obtain the suitable discharge current.

FIG. 8 is a schematic configuration diagram showing the configuration of an eighth embodiment of the light source device according to the present invention. In the excimer light source device 20 (light source device) shown in FIG. 8, the limiting resistor R1 and the correction resistor R2 are connected between the cathode 13 and the DC power supply HV1, and the diode D1 is connected between the anode 14 and the DC power supply HV1.
Excimer light source device 1 shown in FIG.
0 has the same configuration. In the excimer light source device 20 thus configured, the excimer light source device 10
Similarly to the above, it is possible to limit the discharge current to a suitable range and stabilize the glow discharge by each electrode pair.

FIG. 9 is a schematic configuration diagram showing the configuration of a ninth embodiment of the light source device according to the present invention. The excimer light source device 30 (light source device) shown in FIG. 9 includes a device having a pulse generation circuit P as the DC power supply HV1, and a pulse voltage is applied to each electrode pair of the excimer lamp 1 by the DC power supply HV1. . Such excimer light source device 3
According to 0, since the voltage applied to the electrode pair is pulse-shaped, the application of the voltage to the electrode pair is a pulse operation, and the luminous efficiency of excimer light is higher than the continuous operation of continuously applying the voltage. And the peak power is increased. Therefore, the output of excimer light from the excimer lamp 1 can be particularly improved.

FIG. 10 shows a tenth embodiment of the light source device according to the present invention.
It is a schematic structure figure showing the composition of an embodiment. The excimer light source device 40 (light source device) shown in FIG. 10 is different from the excimer light source devices 10, 20, and 30 described above in power supply, and an AC power supply HV2 (power supply) is provided for each electrode pair as a power supply. Connected. The electrodes alternate between the cathode 13 and the anode 14 in accordance with the frequency of the AC power supply HV2 (indicated by reference numerals 13 and 14 in the figure), and the electric field applied between the electrodes also changes in accordance with the frequency. Therefore,
Except that the direction of the electric field periodically changes, the same operation as the above-described pulse operation of the excimer light source device 30 is performed, and the output of the excimer light from the excimer lamp 1 is significantly increased. At this time, although a high-frequency electric field is applied to the electrode pair, since there is an electrode discharge by the internal electrodes, there is almost no possibility that strong high-frequency noise is generated unlike an excimer lamp using a conventional dielectric barrier discharge. .

FIG. 11 shows an eleventh embodiment of the light source device according to the present invention.
It is a schematic structure figure showing the composition of an embodiment. The excimer light source device 50 (light source device) shown in FIG.
The excimer lamp 4 shown in FIG. The basic circuit configuration is the same as that of the excimer light source device 10 shown in FIG. 7, except that the starting circuit 7 is connected between the cathode 43, which is a common electrode, and the DC power supply HV1 without using the starting switch SW2. Is different from the excimer light source device 10.

With the excimer light source device 50 having such a configuration, similarly to the excimer light source device 10, it is possible to maintain a stable glow discharge by good control of the discharge current. Further, since the excimer lamp 4 is used, there is no displacement between the electrodes and no displacement in the parallel direction Y of the cathode.
It is possible to further enhance the stability of glow discharge. Further, since a start switch is not required on the cathode 43 side, the configuration can be simplified. Therefore, since the number of parts is reduced and the excimer lamp 4 having excellent productivity is used, the productivity of the excimer light source device 50 can be improved.

FIG. 12 shows a twelfth embodiment of the light source device according to the present invention.
It is a schematic structure figure showing the composition of an embodiment. The excimer light source device 60 (light source device) shown in FIG. 12 has a limiting resistor R1 and a correction resistor R2 connected between the cathode 43 and the DC power supply HV1, and a diode D1 between the anode 14 and the DC power supply HV1.
Has the same configuration as the excimer light source device 50 shown in FIG. In the excimer light source device 20 thus configured, the excimer light source device 5
Similarly to the case of 0, the discharge current is limited to a suitable range, the glow discharge is stabilized by each electrode pair, and the productivity can be improved.

FIG. 13 shows a thirteenth embodiment of the light source device according to the present invention.
It is a schematic structure figure showing the composition of an embodiment. An excimer light source device 70 (light source device) shown in FIG. 13 has a plurality of electrode pairs connected in parallel to one DC power supply HV1, and the excimer lamp 1 shown in FIG. 1 is used as the excimer lamp. Excimer light source device 7 thus configured
0, it is not necessary to provide a start switch between the cathode 13 and the DC power supply HV1, as in the above-described excimer light source devices 50 and 60 having the cathode 43 as a common electrode, and the number of parts is reduced. Is simplified. Further, in the excimer light source device 70, the DC power supply HV1 is single as compared with the case where the DC power supply HV1 is individually connected to each electrode pair as in, for example, the excimer light source device 10 shown in FIG. Therefore, the device configuration can be further simplified.

FIG. 14 shows a fourteenth embodiment of the light source device according to the present invention.
It is a perspective view which shows a part of structure of embodiment. FIG. 15 is a schematic configuration diagram showing a configuration of a fourteenth embodiment of the light source device according to the present invention. As shown in FIG.
The excimer light source device 80 (light source device) uses an excimer lamp 8 (light source device) shown in FIG. 14 as an excimer lamp. The excimer lamp 8 has two types of cathodes and anodes (cathodes 131, 132 and anodes 141, 142). The anodes 141, 142 have limiting resistances R1, R3 indicating different resistance values, and correction indicating different resistance values. The resistors R2 and R4 are connected. The connection positions of the DC power supply HV1, the diode D1, and the starting circuit 7 are the same as those of the excimer light source device 10 shown in FIG.

In the excimer lamp 8, as shown in FIG. 14, the electrode interval between the cathode 132 and the anode 142 constituting the central electrode pair is arranged on both sides of the three electrode pairs arranged in parallel. It is narrower than the electrode interval between the cathode 131 and the anode 141 constituting the electrode pair. Other configurations are the same as those of the excimer lamp 1 shown in FIG. Further, the resistance circuit composed of the limiting resistor R3 and the correction resistor R4 has a larger resistance value than the resistance circuit composed of the limiting resistor R1 and the correction resistor R2.

The excimer light source device 8 configured as described above
According to 0, since the electrode interval of the electrode pair formed by the cathode 132 and the anode 142 in the excimer lamp 8 is narrower than the other electrode pairs, the glow discharge by this electrode pair is lower than that of the other electrode pairs. Can start with voltage. In this case, the periphery of the electrode pair is ionized by the glow discharge, and the startability of another electrode pair in the vicinity of the electrode pair is enhanced, and as a result, the starting voltage of the other electrode can be reduced. Therefore, the startability of the excimer lamp 8 and the excimer light source device 80 can be improved.

FIG. 16 shows a fifteenth embodiment of the light source device according to the present invention.
It is a schematic structure figure showing the composition of an embodiment. An excimer light source device 90 (light source device) shown in FIG. 16 includes pipes 91 a and 91 in the gas filled container 11 of the excimer lamp 1 shown in FIG.
b, 91c, and 95 are connected, and the raw material gas cylinders 92a, 92b, and 92c and the off-gas recovery container 96 are connected to those pipes, respectively. Raw material gas cylinder 9
2a, 92b and 92c are filled with different types of source gases under pressure. Also, the pipes 91a, 91
On and off valves 93a, 93b and 93c are provided on b and 91c, respectively. A pump 98 and on / off valves 97a and 97b are provided on the pipe 95 upstream and downstream of the pump 98, respectively. Also, the on-off valves 93a, 93
b, 93c, 97a, and 97b are electrically connected to a control device 94 for controlling the opening and closing of these.

The excimer light source device 9 configured as described above
In step 0, as a procedure for sealing the raw material gas in the gas sealing container 11, for example, the following method can be mentioned. First, the pump 98 is operated with the on-off valves 97a and 97b open, and the inside of the gas enclosure 11 of the excimer lamp 1 is evacuated. The gas discharged from the gas filling container 11 is stored in an off-gas recovery container. Next, the on-off valves 97a, 9
After closing 7b, the open / close valves 93a, 93b, 93c are opened, and the respective source gases are supplied to the source gas cylinders 92a, 92b, 92b.
From c, the gas is charged into the gas filled container 11 through the pipes 91a, 91b, 91c, and the on-off valves 93a, 93b, 93c are closed. These on-off valves 93a, 93b, 93c, 97a,
The opening and closing of 97 b is performed by an opening and closing signal from the control device 94. Thus, the pipes 91a, 91b, 91c, the raw material gas cylinders 92a, 92b, 92c, and the on-off valve 93
A, 93b, and 93c constitute a source gas supply means, and a pipe 95, open / close valves 97a and 97b, and a pump 98 constitute a discharge means.

Then, the above operation is repeated, and the on-off valve 9 is opened.
By adjusting the opening / closing amount and opening / closing time of the 3a, 93b, 93c, and changing the type of the raw material gas cylinders 92a, 92b, 92c, the components and concentrations of the mixed gas sealed in the gas sealing container 11 are appropriately adjusted. Becomes possible. As described above, according to the excimer light source device 90, the source gas in the gas sealing container 11 can be replaced, and the source gas composed of a desired mixed gas can be sealed in the excimer lamp 1. Therefore, one excimer light source device 90 can extract excimer light having an emission spectrum corresponding to various uses.

FIG. 17 shows a sixteenth embodiment of the light source device according to the present invention.
It is a perspective view showing typically the structure of an embodiment. The excimer lamp 9 (light source device) shown in FIG. 17 has a partition plate 19 (partition wall) provided between each pair of electrodes, and the other configuration is the same as the excimer lamp 1 shown in FIG. Each partition plate 19 is arranged so as to be substantially orthogonal to the parallel direction Y of the electrode pairs, and the upper and lower portions of each partition plate 19 are respectively formed on the upper wall 12 a lower surface and the bottom wall 12
b It is joined to the upper surface. Thus, each pair of electrodes is isolated from each other by these partition plates 19.

Excimer lamp 9 having such a configuration
According to this, the partition plate 19 sufficiently prevents the discharge occurring at one electrode pair from going to the other electrode pair. Therefore, the glow discharge can be further stabilized. Further, since the partition plate 19 is disposed between the electrode pairs in the parallel direction Y of the electrode pairs, and the partition plate 19 is provided so as to be substantially orthogonal to the parallel direction Y of the electrode pairs, Excimer light emitted by the glow discharge is emitted to the outside from the light transmission window 15 without being blocked by the partition plate 19. Therefore, it is possible to sufficiently prevent the emission area of the excimer light from being reduced and the occurrence of an undesired shadow in the irradiation area of the excimer light.

FIG. 18 shows a seventeenth embodiment of the light source device according to the present invention.
FIG. 19 is a perspective view schematically showing the structure of the embodiment, and FIG.
FIG. 19 is an enlarged view showing a portion A in FIG. 18. As shown in FIG. 18, a plurality of excimer lamps 100 (light source devices) are provided in a hollow rectangular parallelepiped gas enclosure 101 (sealing body) such that a flat cathode 13 and a plurality of anodes 14 face each other. It was done. Thus, the opposing cathode 13
The anode 14 forms a plurality of electrode pairs.
Further, the gas filled container 101 has a U-shaped side wall 101a.
, A pin-side base 102b and a light-transmitting window 103 (light-emitting portion) are joined, and the electrode-side base 102a is disposed in a closed space inside.

A plurality of pins 23 penetrate the electrode-side base 102a and the pin-side base 102b and are arranged in a matrix.
3 and the anode 14 are joined. Further, in each electrode pair, the cathode 13 and the anode 14 are preferably formed so as to satisfy the relationship shown in the above formula (1), similarly to the excimer lamp 1 shown in FIG. Also, the electrode side base 10
A substantially ring-shaped hermetic glass 23a for electrically insulating the pin 23 from the electrode-side base 102a is provided at a portion of the pin 2a and the pin-side base 102b through which the pin 23 passes (the electrode-side base 102a).
(The hermetic glass is not shown).

Further, the light transmitting window 103 is formed on the side wall 101.
a and a quartz window 103 via an aluminum frame 103b on a side wall window frame 103a coupled to the end of the pin side base 102b.
c is joined. This light transmission window 103 is
It is installed so that the angle θ is substantially 90 ° on an extended line X substantially orthogonal to a virtual plane defined by the parallel direction Y of the electrode pairs. A source gas for generating excimer molecules is sealed in the closed space inside the gas sealing container 101 so as to have a predetermined internal pressure. In this state, a predetermined voltage is applied to each electrode pair. ing.

The excimer lamp 100 thus configured
Can be assembled, for example, by the following procedure. (1) A plurality of holes for setting the pins 23 are formed in a flat plate made of Kovar metal (which becomes the electrode side base 102a), and the hermetic glass 23a and the pins 23 made of Kovar metal are heat-sealed to these holes. Airtightly join. (2) The cathode 13 and the anode 14 made of molybdenum are respectively joined to the tips of the pins 23 on the cathode 13 side and the anode 14 side by laser welding. (3) On the Kovar metal plate (pin side base 102b)
The hermetic glass 23a and the pin 23 of the electrode-side base 102a manufactured in the above (1) are hermetically bonded to these installation holes by heat fusion. A hole is provided in one central portion of the pin-side base 102b, and the gas sealed container 1 after assembly is formed in this hole.
An exhaust pipe for reducing the pressure inside and supplying the raw material gas inside 01 is hermetically joined by laser welding, brazing, or the like. As the exhaust pipe, a pipe made of Kovar metal, stainless steel, or the like can be used. (4) A side wall 101a is manufactured by processing a plate made of Kovar metal, stainless steel or the like into a U-shape. (5) The quartz window 103c is bonded to the side wall window frame 103a made of Kovar metal via the aluminum frame 103b by thermocompression bonding to manufacture the light transmission window portion 103. (6) Assemble the parts obtained in the above (1) to (5).
First, the electrode-side base 102a and the pin-side base 102b are arranged inside the side wall 101a such that the cathode 13 and the anode 14 face each other.
Laser welding the end with a. Next, the light transmission window 103 is disposed at the open end so that the quartz window 103c is on the outside, and the end is laser-welded to obtain the gas sealed container 101 in a state where the exhaust pipe is connected. (7) The inside of the gas sealing container 101 is evacuated through the exhaust pipe to reduce the pressure, and then the raw material gas is introduced into the gas sealing container 101. With the inside at a predetermined pressure, the exhaust pipe is cut by pressing (pinch-off seal) and at the same time the cut portion is sealed to obtain the excimer lamp 100 shown in FIG.

The excimer lamp 10 configured as described above
According to 0, the following operation and effect are exerted in addition to the same operation and effect as the excimer lamp 1 shown in FIG.
That is, if the Y direction in the drawing is the column of the electrode pair arrangement, the light transmitting window 103 is parallel to the column of the electrode pair, so that the excimer light emitted in each row of the electrode pair is transmitted through the entire side wall. The light is emitted from the entire surface of the window 103. Therefore, the irradiation area by the emitted excimer light L is significantly expanded.
Further, the electrode pairs are arranged in a matrix, and the positions of the electrode pairs are shifted by half of the arrangement interval of the electrode pairs for each row as shown in the figure, so that the intensity distribution of the emitted excimer light L in the cross section ( Beam profile) can be flattened, and a wide area can be uniformly irradiated.

FIG. 20 shows an eighteenth light source device according to the present invention.
It is a perspective view showing typically the structure of an embodiment. Excimer lamp 110 (light source device) shown in FIG. 20 has eight cathodes 13 arranged on the same circumference so as to penetrate upper wall 12 a, and has eight anodes 14 opposed to these cathodes 13.
Are arranged on the same circumference so as to penetrate the bottom wall 12b. The arrangement interval G3 between each pair of electrodes is set to be larger than the electrode interval G1 between the cathode 13 and the anode 14 in each pair of electrodes, and the other configuration is the same as that of the excimer lamp 1 shown in FIG.

In the excimer lamp 110 having such a configuration, six electrode pairs excluding one electrode pair located closest to the light transmission window 15 and one electrode pair located farthest from the light transmission window 15. Accordingly, three pairs of electrode pairs facing each other in the Y direction are formed. That is, the parallel directions of these three electrode pairs are all Y directions,
The light transmission window 15 is provided on an extension line X that intersects the virtual plane defined by the parallel direction Y. Therefore, the emission area of the excimer light L from the light transmission window 15 can be equal to or larger than the excimer lamp 1 shown in FIG.
The output of the excimer light L can also be increased by increasing the number of electrode pairs. At this time, the pair of the three electrode pairs is
Since they do not overlap in the direction of the extension line X, the intensity distribution (beam profile) of the cross section of the excimer light L is relatively flattened, and uniform irradiation becomes possible.

In each of the above embodiments, the number of electrode pairs is not limited to three, but may be two or four or more. Further, the shapes of the cathode 13 and the anode 14 need not be rod-shaped (column-shaped), but may be prism-shaped. Further, a cathode 13 and an anode 14
Is installed so that their tips face each other,
It may have a bent part. Furthermore, the cathode 4
As long as 3 has a surface 43S facing the anode 14, the overall shape is not limited to a simple flat plate, but may have a folded structure (or a bent portion). In this case, since the surface area of the cathode 43 is increased and the temperature rise is suppressed, arcing of the discharge is sufficiently suppressed. Furthermore, the gas sealing container 11 does not have to be cylindrical, may be prismatic, and may have a branch pipe or the like. Further, the entire gas sealed container 11 is also suitable as a quartz tube (quartz bulb).

Further, the light transmitting window 15 and the optical lens 31 may not be provided so as to project from the outer wall (side wall) of the gas filled container 11 to the outside, but may be provided so as to constitute a part of the side wall. Is the above-mentioned quartz tube, a part of the side wall of the quartz tube can be used as a light emitting portion. Further, the reflecting portion 21 may be such that a reflective coating having high excimer light reflectance is applied to the inner surface of the gas sealing container 11. Further, the reflecting portion 21 may not be in contact with the inner surface of the gas filled container 11. Furthermore, the excimer light source device 90
Is not always necessary, and the operation of the on-off valve may be performed manually. In addition, the excimer lamp 100
May be arranged in a simple grid.

It is also preferable that the structure of the cathode and / or the anode is a heat pipe structure and the cathode and / or the anode are actively cooled. By doing so, the temperature rise of the electrode is further suppressed, and arcing of the discharge can be further suppressed. Further, only a part of the plurality of electrode pairs may be started to cause glow discharge. In this way, a dimming effect can be obtained, and a desired excimer light irradiation density can be obtained by appropriately selecting the number of electrode pairs to be driven and the position of the driven electrode pairs. In addition,
A self-diagnosis function for detecting a circuit including an electrode pair for which glow discharge is not performed during operation (that is, a non-lighting circuit);
It is preferable to provide a unit capable of restarting.
With the provision of such means, the reliability of the light source device can be improved. In this case, the starting circuit 7 may have such a self-diagnosis function. Further, a gas component such as a quenching gas (quenching gas) or a luminescence promoting gas may be added to the source gas.

The light source device according to the present invention is preferably used for compound synthesis or decomposition by various chemical reactions using excimer light, a light source for semiconductor exposure, a light knife for biochemistry, a light source for solar simulation in the field of space chemistry. And the like.

<Production of light source device 1> 3 mm wide as cathode
A single molybdenum plate having a length of 3.2 mm and a thickness of 0.15 mm is used, three nickel pins having a diameter of 1.0 mm are used as anodes, and a thickness of 1 is used as a light transmission window for forming a light emitting portion.
xenon gas as a raw material gas was supplied to the inside of this sealed body at an internal pressure of 93.3 kPa.
(700 torr) to produce an excimer lamp 4 shown in FIG. The distance between the cathode and the anode (electrode distance) was 3 mm. When a DC voltage was applied to the electrodes of the excimer lamp 4 from a constant voltage power supply, glow discharge was started by each electrode pair, and it was visually confirmed that three discharge paths were maintained in a separated state.

<Spectral Spectrum Measurement> In a state where the discharge current flowing between the electrodes of the excimer lamp 4 was set to 3 mA and glow discharge was performed, the spectral spectrum of the excimer light emitted from the light transmission window was set in a vacuum chamber. Photoelectric tube (manufactured by Hamamatsu Photonics Co., Ltd., product name: R122)
0) and a spectrometer. FIG. 21 shows the result. As shown in FIG.
It has a peak near 5 nm and a full width at half maximum (FWHM) of about 2
It was confirmed that excimer light having a continuous spectrum in the vacuum ultraviolet region of 0 nm was output. In the figure,
“Au” represents an arbitrary unit, and indicates that the data value plotted on the graph is a relative value (the same applies hereinafter).

<Measurement of Discharge Current-Excimer Light Output Characteristics>
The excimer light output at a wavelength of 172 nm was measured when the discharge current flowing between the electrodes of the excimer lamp 4 obtained in Example 1 was changed in the range of 2 to 50 mA. FIG. 22 shows a change in the relative output of the excimer light with respect to the discharge current. From FIG. 22, it can be seen that the output of excimer light increases almost linearly with an increase in the discharge current up to a discharge current of about 15 mA. In the region of 2 to 10 mA, this tendency is particularly high and excellent linearity is obtained. Understand. That is, in this region, it was confirmed that stable glow discharge was maintained and the output of excimer light could be controlled well. In contrast, when the discharge current exceeded approximately 15 mA, it was confirmed that the output of excimer light was saturated. That is, in this area,
It is understood that even if the current is increased to increase the input power, it is difficult to increase the output of the excimer light, and the conversion efficiency of the input power to the excimer light decreases.

When the sustaining voltage during discharge was measured at the same time, the sustaining voltage was kept almost constant in a region where the discharge current was up to 15 mA. Negative characteristic).
From this, it is determined that when the discharge current exceeds approximately 15 mA, the glow discharge shifts from a normal glow discharge to an arc discharge through an abnormal glow discharge. From the above results, the excimer lamp 4 has a discharge current region where the glow discharge is stably maintained, and the range of the discharge current is about 1
It was found that it was slightly more than 0 mA, and had a width enough to sufficiently control the output of excimer light. From this, it was confirmed that according to the light source device of the present invention, the glow discharge can be favorably maintained, and a sufficiently stable operation can be performed.

<Production of light source device 2> 7.8 width as cathode
One molybdenum plate of mm × length 9.8 mm × thickness 0.3 mm, three Kovar pins having a diameter of 0.7 mm as an anode, and 1 mm thick synthetic quartz as a light transmission window for forming a light emitting portion Using a plate, xenon gas as a raw material gas is introduced into the inside of the sealed body at an internal pressure of about 6.7-13.
3 kPa (50-1000 torr) (50 torr
Each excimer lamp 4 having the shape shown in FIG. The electrode interval was 2 mm.

<Measurement of Internal Pressure of Source Gas-Excimer Light Output Characteristics> A constant-voltage DC power supply was connected to the electrode pair of each excimer lamp 4 obtained in the above <Production of Light Source Device 2> via a limiting resistor having a resistance value of 50 kΩ. And discharge current between the electrodes is 1 to 10
Glow discharge was generated by changing the current in the range of mA. The output of the excimer light output in this state is converted to a photoelectric tube (manufactured by Hamamatsu Photonics KK, product name:
R4044). The results are shown in FIG.
FIG. 23 is a graph showing an excimer light output characteristic with respect to the internal pressure of the source gas of the excimer lamp 4 obtained in Example 4. A curve L9 in the figure indicates a maximum excimer light output with respect to the internal pressure of the source gas (xenon gas). The curve L10 shows the change in the conversion efficiency with respect to the internal pressure of the source gas.

Here, the “conversion efficiency” is obtained by dividing the measured value of the output voltage value (mV) of the photoelectric tube at the time when the excimer light output becomes maximum by the input power (W) at that time. This is a calculated value, and is shown as a relative value in FIG. FIG. 23 shows that when the internal pressure of xenon gas (source gas) exceeds about 80 kPa (about 600 torr), the maximum value of the excimer light output tends to increase gradually, but this internal pressure is about 13.3 kPa (about 100 torr). Above this, the output of the excimer light is approximately at a constant level (45
~ 55a.u.).

Further, the internal pressure of xenon gas is about 20 to
When the pressure is in the range of 100 kPa (about 150 to 750 torr), the conversion efficiency becomes relatively high. When the internal pressure is about 25 to 70 kPa (about 190 to 530 torr), the conversion efficiency is further increased. . From this, from the viewpoint of maintaining high conversion efficiency, it was confirmed that the internal pressure of the raw material gas was preferably 20 to 100 kPa, more preferably 25 to 70 kPa.

[0099]

As described above, according to the present invention,
Without decreasing the luminous intensity and the illuminance of the excimer light irradiation area, the emission area of the excimer light can be expanded and the irradiation area can be expanded, and the discharge state is stabilized, and a sufficiently stable operation can be performed. , A light source device that cannot be a high-frequency noise source that causes EMI can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically showing a structure of a first embodiment of a light source device according to the present invention.

FIG. 2 is a perspective view schematically showing a structure of a light source device according to a second embodiment of the present invention.

FIG. 3 is a perspective view schematically showing a structure of a third embodiment of the light source device according to the present invention.

FIG. 4 is a perspective view schematically showing a structure of a light source device according to a fourth embodiment of the present invention. FIG. 4 (a) is an overall view of the light source device, and FIG. FIG.

FIG. 5 is a perspective view schematically showing a structure of a light source device according to a fifth embodiment of the present invention.

FIG. 6 is a perspective view schematically showing a structure of a light source device according to a sixth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram illustrating a configuration of a seventh embodiment of a light source device according to the present invention.

FIG. 8 is a schematic configuration diagram showing a configuration of an eighth embodiment of the light source device according to the present invention.

FIG. 9 is a schematic configuration diagram showing a configuration of a ninth embodiment of a light source device according to the present invention.

FIG. 10 is a schematic configuration diagram showing a configuration of a tenth embodiment of a light source device according to the present invention.

FIG. 11 is a schematic configuration diagram showing a configuration of an eleventh embodiment of a light source device according to the present invention.

FIG. 12 is a schematic configuration diagram showing a configuration of a twelfth embodiment of a light source device according to the present invention.

FIG. 13 is a schematic configuration diagram showing a configuration of a light source device according to a thirteenth embodiment of the present invention.

FIG. 14 is a perspective view schematically showing a part of the structure of a light source device according to a fourteenth embodiment of the present invention.

FIG. 15 is a schematic configuration diagram showing a configuration of a fourteenth embodiment of a light source device according to the present invention.

FIG. 16 is a schematic configuration diagram showing a configuration of a fifteenth embodiment of the light source device according to the present invention.

FIG. 17 is a perspective view schematically showing a structure of a light source device according to a sixteenth embodiment of the present invention.

FIG. 18 is a perspective view schematically showing a structure of a light source device according to a seventeenth embodiment of the present invention.

FIG. 19 is an enlarged view showing a portion A in FIG. 18;

FIG. 20 is a perspective view schematically showing a structure of an eighteenth embodiment of the light source device according to the present invention.

FIG. 21 is a graph showing a spectrum of excimer light output from an excimer lamp manufactured in <Production 1 of light source device>.

FIG. 22 is a graph showing a change in a relative output of excimer light with respect to a discharge current in an excimer lamp manufactured in <Production 1 of light source device>.

FIG. 23 is a graph showing an excimer light output characteristic with respect to a source gas internal pressure of an excimer lamp manufactured in <Production 2 of light source device>.

[Explanation of symbols]

1,2,3,4,5,6,8,9,100,110 ... Excimer lamp (light source device), 10,20,30,40,
50, 60, 70, 80, 90: excimer light source device (light source device), 11, 101: gas filled container (sealed body), 1
3, 43, 131, 132 ... cathode, 14, 141, 14
2 ... Anode, 15 ... Light transmission window (light emission part), 19 ... Partition plate (partition wall), 21 ... Reflection part, 31 ... Optical lens (light emission part), 43a ... Convex part, 103 ... Light transmission window part ( Light emitting portion), D1: diode, G1: electrode spacing, HV1: DC power supply (power supply), HV2: AC power supply (power supply), L: excimer light (natural radiation light), P: pulse generation circuit, R1, R
3: Limiting resistance (resistance circuit), R2, R4: Correction resistance (resistance circuit), Sa: anode area, Sc: cathode area, X: extension line (extension line orthogonal to virtual plane), Y: parallel of electrode pairs direction.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Hiroyuki Hisashima 1126 Nomachi, Hamamatsu City, Shizuoka Prefecture 1 Hamamatsu Photonics Co., Ltd. F term (reference) 3K098 AA05 AA30 5C015 HH02 5C039 JJ01

Claims (11)

[Claims] 1. A light source device for ionizing a source gas for generating excimer molecules by glow discharge and extracting spontaneous radiation emitted from the excimer molecules, wherein the source gas is sealed and the spontaneous radiation A light source device comprising: a sealing body provided with a light emitting portion having a light-transmitting property; and at least two electrode pairs disposed inside the sealing body. 2. The method according to claim 1, wherein the electrode pair includes at least one cathode linearly arranged inside the envelope and at least two anodes arranged inside the envelope so as to face the cathode. 2. The light source device according to claim 1, wherein the light emitting unit is provided on an extension that intersects a virtual plane determined in a parallel direction of the electrode pairs. 3. 3. A power supply for applying a voltage to each of the electrode pairs; and a power supply connected between the power supply and at least one of the anode and the cathode, wherein the electrode pairs are connected when the glow discharge is performed. A resistor circuit for limiting the current flowing through
The light source device according to claim 2, further comprising: 4. Connected between the power supply and the anode,
The light source device according to claim 2, further comprising a diode that limits a current flowing through the pair of electrodes when the glow discharge is performed. 5. The light source device according to claim 3, wherein the power supply is a DC power supply that applies a pulse voltage to the electrode pair. 6. The light-emitting device according to claim 1, wherein a reflection portion for reflecting the spontaneously emitted light is provided at a position inside the envelope facing the light emission portion. Light source device. 7. The raw material gas contains at least one of a rare gas, a rare gas halide, and a nitrogen gas, and at least one of a hydrogen isotope gas, a halogen gas, and a mercury vapor. The light source device according to claim 1, wherein the light source device is a mixed gas. 8. The cathode according to claim 2, wherein a projection is formed at a portion facing the anode.
The light source device according to any one of claims 7 to 7. 9. The light source device according to claim 2, wherein the cathode and / or the anode have a surface on which a metal compound layer is provided. 10. An electrode pair in which at least one electrode pair has a smaller electrode interval and a larger resistance value of the connected resistance circuit than other electrode pairs different from the electrode pair. The light source device according to any one of claims 3 to 9, wherein 11. The light source according to claim 1, further comprising a partition wall disposed between the pair of electrodes in a direction parallel to the pair of electrodes and separating the pair of electrodes from each other. apparatus.