JPH08212982A - Microwave discharge light source device - Google Patents

Abstract

PURPOSE: To perform large area, high luminance irradiation by stable discharge and emission. CONSTITUTION: Microwaves oscillated from four microwave oscillators 10-13 are passed through slits 30-32 of a wave guide 18, then made incident on three microwave resonance cavities 33-35 respectively, and excite a discharge luminescent material in a quartz discharge tube 39 to discharge and emit light. By a controller 40, the microwave is alternately or simultaneously oscillated from the four microwave oscillators 10-13 and controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave discharge light source device applied to the field of optical processes such as exposure processing, photochemical application, and photocleaning.

[0002]

2. Description of the Related Art Recently, in the optical process field, in order to further develop into the fields of semiconductors and liquid crystals, high brightness and large area are required as the light source. Currently, a low-pressure mercury lamp is almost used as a light source for large-area irradiation. However, this low-pressure mercury lamp is not a high brightness light source,
Since the wavelength is limited to 185 nm and 254 nm, a microwave discharge excitation type excimer lamp is particularly promising as a light source to replace the low pressure mercury lamp.

In this microwave discharge excitation type excimer lamp, a waveguide 1 as shown in FIG. 2 is connected to a microwave oscillator, and a part of the waveguide 1 or a plane perpendicular to the E plane and the H plane is formed. A slit is provided in the portion, and a cylindrical resonator or a hemispherical resonator having a diameter of, for example, about 15 cm is provided in the slit portion. A spherical discharge vessel having a diameter of about 3 cm is arranged near the center of these cylindrical resonators and hemispherical resonators, and a discharge light emitting substance such as an excimer is enclosed in the discharge vessel.

With such a configuration, the microwave oscillated by the microwave oscillator is guided to the waveguide and enters the cylindrical resonator, for example, through the slit. The incidence of the microwave excites the discharge luminescent material in the discharge container arranged in the cylindrical resonator to generate a discharge, and the discharge light is emitted.

[0005]

However, in such a microwave discharge excitation type excimer lamp, it is difficult to irradiate an object with a uniform illuminance because of a large variation in emission intensity distribution. .

Therefore, an object of the present invention is to provide a microwave discharge light source device capable of stable discharge and light emission. It is another object of the present invention to provide a microwave discharge light source device that can irradiate with high brightness by stable discharge and light emission. Another object of the present invention is to provide a microwave discharge light source device capable of irradiating a large area and high brightness by stable discharge / light emission.

[0007]

According to the first aspect of the present invention, a plurality of microwave oscillators for oscillating microwaves and the microwaves oscillated by these microwave oscillators are connected to each other to generate microwaves. A waveguide to be guided, at least one slit formed on the E surface of the waveguide, a plurality of microwave resonant cavities provided for each slit, and a microwave resonant cavity provided in these microwave resonant cavities. A microwave discharge light source device, which is provided with a lamp in which a discharge luminescent substance that discharges and emits light when excited by a microwave guided by a wave tube is enclosed.

According to a second aspect of the present invention, there is provided control means for alternately controlling the oscillation of the microwave from at least one of the plurality of microwave oscillators. According to the third aspect, the control means is provided for simultaneously oscillating the plurality of microwave oscillators.

According to claim 4, at least one slit is connected to one microwave resonant cavity. According to claim 5, a metal mesh is provided on a part of the microwave resonant cavity.

According to claim 6, the lamp is arranged through a plurality of microwave resonant cavities. Claim 7
According to U.S. Pat. No. 4,962,629, one lamp is arranged for one of the microwave resonant cavities.

According to the eighth aspect, the slit width L is (λg / 2)  (n, where λg is the in-tube wavelength of the microwave traveling in the waveguide and n and m are integers (n ≦ m). -0.5) ≤ L ≤ (λg / 2) ・
It is set to (m + 0.5).

According to the ninth aspect, a stub tuner is provided in the waveguide, and the length of the stub tuner or the waveguide is adjusted to control the power supply of microwaves guided to the microwave resonant cavity.

[0013]

According to the first aspect of the present invention, the microwaves oscillated by the plurality of microwave oscillators are guided by the waveguide, and further incident on the plurality of microwave resonance cavities through at least one slit to cause resonance and excitation. , The discharge luminescent material in the lamp provided in these microwave resonant cavities is excited to discharge and emit light. Thereby, the discharge light-emitting material in the lamp can be stably discharged and emitted by the microwave, and a plurality of microwave resonant cavities can be arranged in a single waveguide to arrange a plurality of light sources.

According to the present invention, by alternately controlling the oscillation of microwaves from at least one microwave oscillator, it is possible to take out light with high brightness almost continuously and to form a plurality of microwave resonant cavities. It is possible to correct the difference in the light intensity from each microwave resonant cavity that is expected when arranged.

According to the third aspect, simultaneous irradiation of a large area becomes possible by simultaneously oscillating a plurality of microwave oscillators. According to the fourth aspect, by connecting one microwave resonance cavity body to at least one slit, it is possible to improve the selectivity of the microwave resonance mode.

According to the fifth aspect, by providing the metal mesh in the opening of the microwave resonant cavity, the light emitted from the microwave resonant cavity can be efficiently extracted. According to the sixth aspect, a long cylindrical discharge can be obtained by disposing the lamp through the plurality of microwave resonant cavities.

According to the seventh aspect, by arranging one lamp for one microwave resonant cavity, it is possible to emit light of high brightness. According to claim 8, the slit width L is set to (λg / 2) · (n−0.5) ≦ L ≦ (λg / 2) ·
By setting (m + 0.5), a plurality of microwave resonant cavities can be made to emit light at the same time by a single microwave,
Large area simultaneous irradiation is possible.

According to the ninth aspect, a stub tuner is provided in the waveguide, and the length of the stub tuner or the waveguide is adjusted to control the electric power supply of the microwave guided to the microwave resonant cavity. Electric power is supplied to the microwave resonant cavity by a single microwave oscillator, and a large amount of electric power can be emitted from a lamp to emit light with a large area and high brightness.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a microwave discharge light source device. This device is used as a microwave discharge excitation KrCl excimer lamp (wavelength 222 nm).

Each of the four microwave oscillators 10 to 13 has a pulse repetition frequency of 1 kHz with a duty of 25%.
It has a function of oscillating a pulsed microwave of z. A common waveguide 18 is connected to these microwave oscillators 10 to 13 via waveguides 14 to 17 of each branch.

Each of the waveguides 14 to 17 has an isolator 19 to 22 and a stub tuner 23 to 26, respectively.
Is provided. Of these, each isolator 19-22
Are arranged to protect each microwave oscillator 10 to 13 from a reflected wave traveling toward its own microwave oscillator 10 to 13 and a traveling wave from another microwave oscillator 10 to 13.

Three slits 30 to 32 are formed on the E surface of the waveguide 18. These slits 30
˜32, the slit width L is λg for the in-tube wavelength of the microwave traveling in the waveguide 18 and n, m for integers (n ≦
m), (λg / 2) · (n−0.5) ≦ L ≦ (λg / 2) · (m + 0.5) (1).

Microwave resonant cavities 33 to 35 are connected to the slits 30 to 32, respectively. These microwave resonant cavities 33 to 35 are formed in a cylindrical shape, and metal meshes 36 to 38 are provided in their openings, respectively.

The microwave resonant cavities 33 to 3 are also provided.
In FIG. 5, a quartz discharge tube 39 is provided so as to communicate with these microwave resonant cavities 33 to 35. This quartz discharge tube 39 is filled with 100 Torr gas containing Kr of 1%, HCl of 1% and He as a buffer gas as a discharge luminescent material.

On the other hand, the control device 40 has a function of alternately controlling the oscillation of microwaves from at least one of the four microwave oscillators 10 to 13, and for example, the four microwave oscillators 10 to 13 are used. For each delay time 0μsec, 250μsec, 500μs
It has a function of setting ec and 750 μsec to alternately control the microwave oscillation.

Further, the control device 40 includes slits 30 to 32.
When the slit width L is formed so as to satisfy the above expression (1), the four microwave oscillators 10 to 13 have a function of simultaneously oscillating and controlling microwaves.

Next, the operation of the device configured as described above will be described. The microwaves oscillated and output from the four microwave oscillators 10 to 13 are the isolators 19 to 22 of the waveguides 14 to 17 and the stub tuners 23 to 2 respectively.
The three microwave resonance cavities 33 to 35 are excited by the three slits 30 to 32 which are guided to the waveguide 18 through 6 and formed on the E surface of the waveguide 18.

The microwave resonant cavities 33 to 35 resonate by the microwave power at this time, and the discharge luminescent material in the quartz discharge tube 39 is excited and discharged. This quartz discharge tube 3
The light emitted by the discharge of 9 is
It is taken out through 38.

The light thus emitted has a long cylindrical shape because the quartz discharge tube 39 is provided by connecting the three microwave resonant cavities 33 to 35. Moreover, since the light is extracted to the outside through the metal meshes 36 to 38, the emitted light can be extracted efficiently.

On the other hand, the control unit 40 delays each of the four microwave oscillators 10 to 13 with a delay time of 0 μsec.
Microwave oscillation is controlled alternately by setting 50 μsec, 500 μsec, and 750 μsec.

Therefore, four microwave oscillators 10-1
Microwaves are sequentially oscillated and output from 3 in accordance with the delay time, and the three microwave resonant cavities 33 to 35 are sequentially excited by these microwave powers, and the discharge luminescent material in the quartz discharge tube 39 is excited and discharged. Then, the light is extracted to the outside through the metal meshes 36 to 38. As a result, light with high brightness is extracted almost continuously.

Further, the control device 40 includes slits 30 to 32.
When the slit width L is formed so as to satisfy the above formula (1), the microwaves are simultaneously controlled from the four microwave oscillators 10 to 13.

When microwaves are simultaneously oscillated and output from the microwave oscillators 10 to 13, three microwave resonant cavities 33 to 35 are generated by these microwave powers.
Are excited at the same time, the discharge luminescent material in the quartz discharge tube 39 is excited and discharged, and the light is extracted to the outside through the metal meshes 36 to 38.

That is, the three microwave resonant cavities 3
3 to 35 are excited by a single microwave (traveling wave) at the same time to emit light, whereby light is simultaneously emitted in a large area.

On the other hand, each of the slits 30 to 32 has the above formula (1).
If the slit width L is not satisfied, the waveguide lengths of the waveguides 14 to 18 and the stub tuners 23 to 26 are satisfied.
Adjust the conditions of.

By these adjustments, it becomes possible to supply electric power to one microwave resonance cavity body, for example 33, by microwaves by one microwave power source. As a result, high-power, high-luminance light emission with high repetition is achieved.

As described above, in the above embodiment, the microwaves oscillated by the four microwave oscillators 10 to 13 are incident on the three microwave resonant cavities 33 to 35 through the slits of the waveguide 18. Since the discharge luminescent material in the quartz discharge tube 39 is excited to discharge and emit light, the discharge luminescent material in the quartz discharge tube 39 can be stably discharged and emitted by the microwave, and high-intensity light is emitted. it can.

Further, by arranging the three microwave resonant cavities 33 to 35 in the waveguide 18, it is possible to obtain three light sources. Therefore, if the number of arranged microwave resonant cavities is increased, The quartz discharge tube 39, that is, the lamp length can be extended.

Furthermore, four microwave oscillators 10-1
By alternately oscillating and controlling the microwaves from 3, the high-luminance light can be taken out almost continuously, and each microwave resonance cavity expected when a plurality of microwave resonance cavity bodies 33 to 35 are arranged. The difference in light intensity from the bodies 33 to 35 can be corrected.

One for each slit 30 to 32.
By connecting the three microwave resonance cavities 33 to 35, the selectivity of the resonance mode of the microwave can be improved.
Further, by setting the slit width L so as to satisfy the above expression (1), the three microwave resonant cavities 33 to 33-
35 can be simultaneously made to emit light by a single microwave, and high-intensity large-area simultaneous irradiation becomes possible.

On the other hand, when the slit width L does not satisfy the above equation (1), the stub tuners 23 to 26 and the waveguide length are adjusted to control the power supply of microwaves guided to the microwave resonant cavities 33 to 35. As a result, electric power is supplied to one microwave resonance cavity body by one microwave oscillator, and the lamp can be emitted by a large amount of electric power and a large area and high brightness light can be emitted.

However, by changing the conditions of the slit width L, the waveguide length, and the stub tuners 23 to 26,
Simultaneous high-intensity light emission and high-repetition high-intensity light emission can be performed by two microwave resonant cavities.

Further, since the respective waveguides 14 to 17 are provided with the respective isolators 19 to 22, respectively, the reflection traveling toward the magnetron in each of the microwave oscillators 10 to 13 or another microwave oscillator 10 is provided. The microwaves 10 to 13 can be protected by eliminating the influence of the traveling waves oscillated from 13 to 13 and the life of these devices can be extended.

The present invention is not limited to the above-mentioned embodiment, but may be modified as follows. For example, although the quartz discharge tube 39 used is a closed lamp as the lamp, this lamp may adopt a method of circulating or discharging the discharged luminescent material. It can be extended to about 1000 hours.

The discharge luminescent material is not limited to the KrCl excimer lamp, but KrF, CO ₂ or Xe, Kr, He,
A gas containing Ar, F, Hg or the like may be used. Further, a lamp such as a quartz discharge tube does not communicate between the microwave resonant cavities 55 to 59 as shown in FIG. 3, but is connected to the microwave resonant cavities 55 and 56 as shown in FIG. Of the microwave resonant cavities 57 to 59.
Alternatively, the other lamp 61 may be communicated with the split lamp. Even with such a configuration, the same effect as that of the above-described embodiment can be obtained.

Further, the lamp such as a quartz discharge tube may be of a split type lamp in which one lamp 65 to 67 is provided for each microwave resonant cavity 62 to 64 as shown in FIG.

[0047]

As described above in detail, according to the present invention, it is possible to provide a microwave discharge light source device capable of stable discharge and light emission. Further, according to the present invention, it is possible to provide a microwave discharge light source device capable of high-intensity irradiation by stable discharge / light emission. Further, according to the present invention, it is possible to provide a microwave discharge light source device capable of irradiating a large area and high brightness by stable discharge and light emission.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a microwave discharge light source device according to the present invention.

FIG. 2 is a diagram showing an E surface and an H surface of a waveguide.

FIG. 3 is a configuration diagram showing an arrangement example of lamps with respect to a microwave resonant cavity.

FIG. 4 is a configuration diagram showing an arrangement example of lamps with respect to a microwave resonant cavity.

[Explanation of symbols]

10 to 13 ... Microwave oscillator, 14 to 18 ... Waveguide,
19-22 ... Isolator, 23-26 ... Stub tuner, 30-32 ... Slit, 33-35 ... Microwave resonance cavity body, 36-38 ... Metal mesh, 39 ... Quartz discharge tube, 40 ... Control device.

Claims (9)

[Claims] 1. A plurality of microwave oscillators for oscillating microwaves, a waveguide for connecting the microwave oscillators to each other to guide the microwaves oscillated by the microwave oscillators, and a waveguide in the waveguide. At least one slit formed on the E-plane, a plurality of microwave resonant cavities provided for each slit, and a plurality of microwave resonant cavities provided in these microwave resonant cavities and guided by the waveguide. A microwave discharge light source device comprising: a lamp in which a discharge luminescent substance that discharges and emits light when excited is enclosed. 2. The microwave discharge light source device according to claim 1, further comprising control means for alternately controlling oscillation of microwaves from at least one microwave oscillator of the plurality of microwave oscillators. 3. The microwave discharge light source device according to claim 1, further comprising control means for simultaneously oscillating a plurality of microwave oscillators. 4. The microwave discharge light source device according to claim 1, wherein at least one slit is connected to one microwave resonance cavity body. 5. The metal mesh is provided on a part of the microwave resonant cavity body, as claimed in claim 1.
Alternatively, the microwave discharge light source device according to item 3. 6. The lamp according to claim 1, wherein the lamp is arranged in communication with a plurality of microwave resonant cavities.
Alternatively, the microwave discharge light source device according to item 3. 7. One for each microwave resonant cavity.
The microwave discharge light source device according to claim 1, 2 or 3, wherein two lamps are arranged. 8. The slit width L is (λg / 2) · (n−0.5), where λg is the in-tube wavelength of the microwave traveling in the waveguide and n and m are integers (n ≦ m). ≦ L ≦ (λg / 2) ・
The microwave discharge light source device according to claim 1, 2 or 3, wherein (m + 0.5) is set. 9. The waveguide is provided with a stub tuner, and the length of the stub tuner or the waveguide is adjusted to control the power supply of microwaves guided to the microwave resonant cavity. Alternatively, the microwave discharge light source device according to item 3.