JP5454842B2 - High repetition rate high power excimer laser equipment - Google Patents

Description

  The present invention relates to a high repetition high power excimer laser device, and more particularly to an excimer laser for an exposure apparatus.

As semiconductor devices are highly integrated, excimer laser devices are used as light sources for semiconductor exposure apparatuses.
In recent years, in order to improve the throughput of the exposure apparatus and make the circuit pattern ultra-fine, as shown in Patent Document 1, Patent Document 2, etc., the output is increased by a double chamber system including an oscillation stage laser and an amplification stage laser. Is measured.
In the future, as the integration of semiconductor devices progresses and the node process becomes 32 nm, the exposure apparatus needs to increase the NA (1.3 to 1.5) by the immersion technique and introduce techniques such as double patterning. In order to increase the throughput of this 32-nm node exposure apparatus, an ArF excimer laser is required to have a high repetition frequency (10 kHz or more) and a high output (100 W or more).

  The double chamber system is composed of an oscillation stage laser that produces laser light with high light quality (spectral performance, etc.) and small output, and an amplification stage laser that amplifies the laser light. The form of the double chamber system is roughly classified into a MOPA (Master Oscillator Power Amplifier) system in which no resonator mirror is provided in the amplification stage chamber and a MOPO (Master Oscillator Power Oscillator) system in which a resonator mirror is provided.

A light source for an exposure apparatus for a 32 nm node process is required to have a repetition frequency of 10 kHz or more.
In general, an operable repetition frequency in an excimer laser is described in relation to a clearance ratio (CR). The clearance ratio (CR) is expressed by the following equation where the inter-electrode gas flow velocity is V, the discharge sensation time is t, and the discharge width is W.
CR = Vt / W (1)
When the clearance ratio (CR) is large, stable discharge can be obtained.
The required clearance ratio (CR) value varies depending on the application of the laser, but about 2 or more is required.
In applications where high energy stability is required, such as a light source for a semiconductor exposure apparatus, a large clearance ratio (CR) is required.

From the equation (1), when the repetition frequency is increased from the current 6 kHz to 10 kHz, the discharge interval time t is shortened from 167 μsec to 100 μsec. In order to ensure the same CR value, it is necessary to increase the inter-electrode gas flow velocity V by 1.67 times or the discharge width W to 1 / 1.67.
In Patent Document 3, a high repetitive operation of 10 kHz or more is achieved by reducing the discharge width (W).
As another method for realizing high repetitive operation, two pairs of electrodes are arranged in a resonator of an amplification stage laser in Patent Document 4 in a single chamber system and in Patent Document 3 and Patent Document 5 in a double chamber system. Thus, a method of alternately oscillating the discharge by shifting it by a half cycle is shown. For example, if two pairs of electrodes are arranged in a chamber in which a necessary CR value is obtained in 5 kHz operation and oscillates alternately, operation at 10 kHz is possible.

JP 2001-156367 A JP 2001-24265 A JP 2008-78372 A JP-A-63-98172 U.S. Pat. No. 7,600,547

In a laser apparatus that realizes a high repetitive operation by arranging two pairs of electrodes in the same resonator and alternately oscillating, the length of each electrode is less than half that of a pair. This is because electrical insulation with an insulating material is necessary between the electrodes on the high voltage side. Further, in order to generate and maintain a uniform glow discharge in each electrode pair, it is necessary to generate (preliminarily ionize) electrons having a certain density or more in advance in the discharge space.
As a preionization source, ultraviolet light, corona discharge, X-rays, and the like are used. In the case of alternating oscillation, the preionization source is divided and the discharge space is preionized before the discharge at each electrode pair. At this time, for example, in the case of corona discharge, when the corona discharge is performed by applying a high voltage pulse to the preionization electrode of one preionization source, the preionization electrode of the other preionization source is at the ground potential.

Therefore, it is necessary to maintain this potential difference insulation between the preionization electrodes to which the high voltage pulse of each preionization source is applied. Here, if the creeping distance between the preionization electrodes is increased in order to maintain insulation, the space of the insulating portion between the electrodes on the high voltage side becomes longer and the electrode length becomes shorter.
In general, when laser light having an energy of I ₀ passes through a gain region (gain length L) having a small signal gain coefficient g and an absorption coefficient α, it is amplified to I shown in the following equation.
I = I ₀ × exp {(g−α) L} (2)
To increase the output, we want to make the electrode length proportional to the gain length as long as possible. For this reason, there is a demand for the insulation between the preionization electrodes of the preionization source to be within the space of the insulation part between the electrodes on the high voltage side.

  The present invention has been made in view of such circumstances, and in an excimer laser device that alternately oscillates by arranging two pairs of electrodes in the same resonator, between the electrodes of the preliminary ionization source corresponding to each electrode pair. It is an object of the present invention to provide an excimer laser device having a high repetition rate and a high output, with an insulating structure that can be accommodated in a space of an insulating portion between electrodes on the high voltage side.

In an excimer laser device that alternately oscillates by arranging two pairs of electrodes in the same resonator, insulation between the electrodes of the preliminary ionization source corresponding to each electrode pair is performed in the space of the insulation portion between the electrodes on the high voltage side. The structure fits in.
For example, in a configuration in which a preionization electrode is disposed inside and outside an alumina ceramic pipe and corona discharge is applied, when applying a high voltage pulse to the inner preionization electrode, by sealing the central portion, a short distance can be obtained. Insulation can be secured.
Although it is possible to increase the creepage distance by providing a fold or the like inside the central portion, it is very difficult to manufacture. When a high voltage pulse is applied to the outer preionization electrode, it is possible to provide a fold or the like on the outer periphery of the alumina ceramic pipe to increase the insulation distance.
In the excimer laser device that alternately oscillates by arranging two pairs of electrodes in the same resonator, the insulation is ensured by sealing or folding the central part of the alumina ceramic pipe of the preliminary ionization source. In addition, a high repetition and high power excimer laser device is realized.
That is, in the present invention, the above problem is solved as follows.
(1) A laser chamber in which a laser gas is sealed, a plurality of electrode pairs that are arranged along the optical path of laser light inside the laser chamber, and are opposed to each other with a predetermined spacing, and each of the electrodes A power supply circuit for discharging a pair, a pulsed voltage is sequentially applied from the power supply circuit to the plurality of electrode pairs, and discharge is sequentially generated between the plurality of electrode pairs at a predetermined time interval. In the output pulse gas laser device, a cylindrical insulator including a hollow cylindrical portion disposed adjacent to one electrode of each electrode pair, and a preliminary ionization disposed in an inner layer of the cylindrical portion, respectively. an inner electrode, and an outer layer arranged preionization outside electrode of said cylindrical portion, redundant power to generate a corona discharge by a voltage being applied between the preionization inside electrode and the preionization outer electrode Comprising a mechanism, and an insulating material interposed between the adjacent said preionization inside the electrode or between the pre-ionization outer electrode voltage of the high-pressure side is applied in the preliminary ionization mechanism adjacent said preionization inside electrode It is formed of a plate-shaped conductor .
In (2) above (1), each preionization mechanism is disposed adjacent to an electrode on the ground side potential of the respective electrode pair, the preliminary arranged on the outer side of the cylindrical portion of each preionization mechanism The ionization outer electrode is set to the ground side potential, a high voltage is applied to the preliminary ionization inner electrode arranged on the inner layer side, and the cylindrical insulator is divided for each preliminary ionization mechanism, and the adjacent preliminary ionization mechanism is divided. It is characterized by comprising an insulator that is disposed apart from one another between the mechanisms and that is disposed at a portion facing another adjacent cylindrical insulator.
(3) In the above (1), each preionization mechanism is disposed adjacent to an electrode on the ground side potential of the respective electrode pair, the preliminary arranged on the outer side of the cylindrical portion of each preionization mechanism The ionization outer electrode is set to the ground side potential, a high voltage is applied to the preliminary ionization inner electrode disposed on the inner layer side, and the cylindrical insulator is connected between adjacent preliminary ionization mechanisms and adjacent to the adjacent ionization mechanism. It is characterized by comprising an insulator disposed between the preliminary ionization inner electrodes on the inner layer side between the preliminary ionization mechanisms.
(4) In the above (1), each preionization mechanism is disposed adjacent to the electrodes of the high pressure side potential of the respective electrode pair, the preliminary arranged on the inner side of the cylindrical portion of each preionization mechanism The ionization inner electrode is set to ground potential, a high voltage is applied to the preliminary ionization outer electrode arranged on the outer layer side, and the cylindrical insulator is divided for each preliminary ionization mechanism, and the adjacent preliminary ionization mechanism is divided. It is characterized by comprising an insulator that is disposed apart from one another between the mechanisms and that is disposed at a portion facing another adjacent cylindrical insulator.
(5) In the above (1), each preionization mechanism is disposed adjacent to the electrodes of the high pressure side potential of the respective electrode pair, the preliminary arranged on the inner side of the cylindrical portion of each preionization mechanism The ionization inner electrode is set to the ground side potential, a high voltage is applied to the preliminary ionization outer electrode disposed on the outer layer side, and the insulator of the cylindrical portion is connected between adjacent preliminary ionization mechanisms, An insulating pleat is disposed between the preliminary ionization outer electrodes on the outer layer side between the preliminary ionization mechanisms.

In the present invention, the following effects can be obtained.
(1) In an excimer laser device that alternately oscillates by arranging two pairs of electrodes in the same resonator, a preionization mechanism is arranged such that conductors are arranged in an inner layer and an outer layer with a cylindrical insulator sandwiched between them. When a voltage is applied between them to generate corona discharge, and a high voltage pulse is applied to the preionized inner electrode, the central part of the cylindrical insulator such as alumina ceramic is sealed or divided and sealed. Since this is stopped, it is possible to ensure preionization insulation in the space of the insulating portion between the electrodes. For this reason, a high-repetition and high-power excimer laser device can be realized without shortening the length of the electrode or enlarging the chamber.
(2) In an excimer laser device that alternately oscillates by arranging two pairs of electrodes in the same resonator, a preionization mechanism is arranged by arranging conductors in an inner layer and an outer layer with a cylindrical insulator interposed therebetween, and the conductor When a high voltage pulse is applied to the preionization outer electrode by applying a voltage between them and generating a corona discharge, the alumina ceramic pipe is divided and sealed to provide a space between the pipes, or Since the creepage distance is increased by providing a pleat at the center of the alumina ceramic pipe, pre-ionization insulation can be secured in the space of the insulation between the electrodes, realizing a high repetition rate and high output excimer laser device. be able to.

(1) First Embodiment FIG. 1 shows a configuration diagram of a laser apparatus according to a first embodiment of the present invention. FIG. 1A shows a side sectional view of the laser device taken along a plane parallel to the optical axis of the laser beam, and FIG. 1B shows a sectional view taken along a plane perpendicular to the optical axis of the laser beam. .
The laser device includes a chamber 30, high voltage pulse generators 33 and 34, a rear mirror 36, and a front mirror 37.
The configuration and function of the laser device will be described.
Inside the chamber 30, there are provided two pairs of electrodes (cathode electrode and anode electrode) 30a and 30b, 30c and 30d, which are separated by a predetermined distance and whose longitudinal directions are parallel to each other and whose discharge surfaces face each other. . The chamber 30 is filled with argon (Ar) gas, fluorine (F ₂ ) gas, and buffer gas neon (Ne). The buffer gas may be helium (He).
Further, a preionization mechanism including alumina ceramic pipes 40a and 40b is provided adjacent to the two pairs of electrodes 30a and 30b, 30c and 30d.

When a high voltage pulse is applied to the electrodes 30a and 30b by a power source composed of a high voltage pulse generator 33 and a charger (not shown), a discharge occurs between the electrodes 30a and 30b, and an ArF excimer is generated. It is formed.
Then, it resonates with a resonator composed of a rear mirror 36 and a front mirror 37, and laser light is output from the front mirror 37.
Next, when a high voltage pulse is applied to the electrodes 30c and 30d by a power source including a high voltage pulse generator 34 and a charger (not shown), a discharge occurs between the electrodes 30c and 30d, and an ArF excimer is formed. The
Then, it resonates with a resonator composed of a rear mirror 36 and a front mirror 37, and laser light is output from the front mirror 37. The discharge at the two pairs of electrodes 30a and 30b, 30c and 30d is repeated alternately.
Note that the rear mirror 37 may be a module that narrows the spectral width composed of a magnifying prism and a grating (diffraction grating) that is a wavelength selection element.

Since high voltage pulses are applied to the electrodes 30a and 30c, which are the main discharge electrodes, insulation from the ground is maintained by the insulating material 39 (alumina ceramic). The insulation between the electrode 30a and the ground (the chamber 30 is ground potential) is the creeping surface 60 of the insulating material 39, the insulation between the electrodes 30a and 30c is the creeping surface 61 of the insulating material 39, and the insulation between the electrode 30c and the ground is the insulating material 39. It is maintained at the creepage 62.
Since the electrodes 30a and 30b and 30c and 30d are alternately discharged repeatedly, when discharging between the electrode pairs 30a and 30b, the electrode 30c is at the ground (ground) potential. For this reason, the creepage distance of the creeping surface 61 is the same as the creepage distance of the creeping surfaces 60 and 62. The creeping surfaces 60, 61, and 62 are not flat surfaces, but are provided with unevenness by, for example, ribs, and the necessary creeping distance is secured by a short linear distance. (Not shown).

Further, inside the chamber 30, a cross flow fan 51, a heat exchanger 52, gas flow guides 53 and 54, a temperature sensor and a window (not shown) are provided.
The cross flow fan 51 circulates the laser gas in the chamber 30 and replaces the gas between the electrodes 30a and 30b and between 30c and 30d. The heat exchanger 52 performs exhaust heat in the chamber 30. The temperature sensor is a monitor for controlling to a desired temperature because energy changes depending on the gas temperature.
The window is provided on the output portion of the chamber 30 on the optical axis of the laser beam. The material of the window is CaF ₂ that is transparent to the wavelength of 193 nm of the laser beam.

FIG. 2 is a configuration diagram of the preionization electrode according to the first embodiment, FIG. 2A is a cross-sectional view taken along a plane perpendicular to the longitudinal direction of the electrode, and FIG. 2B is a cross-sectional view of FIG. It is AA sectional drawing of). Moreover, FIG.2 (c) is BB sectional drawing of Fig.2 (a).
As shown in FIG. 2, the preionization electrode is formed of a single-end-sealed alumina ceramic pipe 40a, 40b, preionization inner electrodes 41a, 41b formed of a round bar-shaped conductor, and a conductor. It consists of plate-shaped preionization outer electrodes 42a and 42b.
One-end sealed alumina ceramic pipes 40a and 40b are arranged with the sealing sides facing each other and spaced apart, and the alumina ceramic pipes 40a and 40b and round bar-shaped preionized inner electrodes 41a and 41b are connected to the electrodes 30b and 30d. Adjacent to each other, the pipes 40a and 40b are connected to the electrodes 30b and 30d via the preliminary ionization outer electrodes 42a and 42b.

  In the preionization mechanism of this embodiment, as described above, the conductors 41a, 41b and 42a, 42b are arranged on the inner layer and the outer layer with the cylindrical insulators 40a, 40b interposed therebetween, and a voltage is applied between the conductors. In the example of FIG. 2, since the electrodes 30b and 30d to which the outer layer conductors (pre-ionization outer electrodes 42a and 42b) are connected are at the ground potential, the outer layer conductors 42a, 42b becomes a ground potential, and a negative high voltage pulse is applied to the inner conductors (pre-ionization inner electrodes 41a and 41b) in the same manner as the electrodes 30a and 30c.

FIG. 3 shows a configuration example of an electric circuit in the chamber portion.
As shown in FIG. 3, a peaking capacitor Cp to which a high voltage pulse is supplied from high voltage pulse generators 33 and 34 is provided in the chamber 30, and electrodes 30a, 30c, 30b, and 30d are provided in parallel to the peaking capacitor Cp. And the series circuit of the preionization capacitor Cc and the preionization mechanism 400 are connected.
When a high voltage pulse is applied to the preionization inner electrode 41a from the high voltage pulse generator 33 via the preionization capacitor Cc, corona discharge occurs between the preionization inner electrode 41a and the preionization outer electrode 42a. The gas in the discharge space of the electrode pair 30a, 30b is preionized by the corona discharge light at the time.
Similarly, when a high voltage pulse is applied to the preionization inner electrode 41b from the high voltage pulse generator 34, corona discharge occurs between the preionization inner electrode 41b and the preionization outer electrode 42b, and the electrode is generated by corona discharge light at this time. The gas in the discharge space of the pair 30c, 30d is preionized.

Here, since the area of the corona discharge is determined by the lengths of the preionization inner electrodes 41a and 41b, the preionization inner electrodes 41a and 41b have a length satisfying the following expression (2).
[Discharge length] <[electrode length in preliminary ionization] <[electrode length] (2)
This is because the dielectric strength of the insulating portion is reduced when the corona discharge region is applied to the creeping surfaces 60, 61, 62 (see FIG. 1). When the dielectric strength is reduced, the electrode length is shortened in order to increase the creepage distance.
In the first embodiment, the insulation of the preionization inner electrodes 41a and 41b of the respective preionization sources is ensured by dividing and sealing the alumina ceramic pipes 40a and 40b. Thereby, even if the creeping distance of the creeping surface 61 is the same as the creeping distance of the creeping surfaces 60 and 62, the alternating oscillation operation can be realized.

FIG. 4 shows a configuration diagram of another preliminary ionization electrode according to the first embodiment. 2 is a cross-sectional view taken along line AA corresponding to FIG. 2B, and the preliminary ionization outer electrodes 42a and 42b are not shown.
The difference between FIG. 4 and the first embodiment is that the alumina ceramic pipe is not divided and is integrated and sealed in the vicinity of the central portion.
That is, as shown in FIG. 4, round bar-shaped preionization inner electrodes 41a and 41b are inserted from both sides into a cylindrical alumina ceramic pipe 40 provided with a sealing portion 40c at the center, and preionization is performed. The other structure in which the sealing portion 40c is interposed between the inner electrodes 41a and 41b is the same as that shown in FIG. 2, and an alumina ceramic pipe 40 and a round bar-shaped preionized inner electrode 41a, 41b is disposed adjacent to the electrodes 30b and 30d and substantially parallel to the longitudinal direction of the electrodes 30b and 30d, and the pipe 40 is connected to the electrodes 30b and 30d by a pair of preionized outer electrodes (not shown). Yes.
In the present embodiment, the insulation of the preionized inner electrodes 41a and 41b is secured by the sealing portion 40c provided at the center portion of the alumina ceramic pipe, whereby the creepage distance of the creeping surface 61 is made the creepage distance of the creeping surfaces 60 and 62. Even in the same manner, an alternating oscillation operation can be realized.

(2) Second Embodiment FIG. 5 shows a configuration diagram of a preionization electrode according to a second embodiment of the present invention. 5A is a cross-sectional view taken along a plane perpendicular to the longitudinal direction of the electrode, and FIG. 5B is a cross-sectional view taken along the line AA of FIG. 5A. FIG.5 (c) is BB sectional drawing of Fig.5 (a). FIG. 6 shows an electric circuit of the chamber portion.
The difference between the present embodiment and the first embodiment is that a high voltage pulse is applied to the preliminary ionization outer electrodes 42a and 42b.
As in the first embodiment, the preionization mechanism of the present embodiment has conductors 41a, 41b and 42a, 42b arranged between inner and outer layers with cylindrical insulators 40a, 40b sandwiched between the conductors. A voltage is applied to generate a corona discharge. As shown in FIG. 6, the inner preliminary ionization inner electrodes 41a and 41b are set to the ground potential, and the outer preliminary ionization outer electrodes 42a and 42b are connected to the electrodes 30a and 42a. Connected to 30b, a high voltage pulse is applied.

Insulation of the preionization outer electrodes 42a and 42b of each preionization source divides the alumina ceramic pipes 40a and 40b, seals one end, and separates the sealing side of the pipes 40a and 40b sealed at one end. Insulation is ensured by placing them facing each other.
That is, by providing a space of about 30 mm between the pipes 40a and 40b, insulation of the preliminary ionization outer electrodes 42a and 42b is ensured, thereby making the creepage distance of the creeping surface 61 the same as the creepage distance of the creeping surfaces 60 and 62. However, an alternating oscillation operation can be realized.

Next, FIG. 7 shows a configuration diagram of another preliminary ionization electrode which is a modification of the second embodiment. This figure is an AA sectional view corresponding to FIG. 5B, and the preliminary ionization outer electrodes 42a and 42b are not shown.
The difference between FIG. 7 and the second embodiment is that a crease 43 is provided at the center of the alumina ceramic pipe 40 to increase the creepage distance and to ensure insulation of the preliminary ionization outer electrodes 42a and 42b. .
That is, as shown in FIG. 7, a cylindrical alumina ceramic pipe 40 is arranged substantially parallel to the electrodes 30b and 30d, and a single preionized inner electrode 41a is inserted into the alumina ceramic pipe 40, The preionized inner electrode 41a is set to the ground potential. The preionized outer electrodes 42a and 42b are separated from each other and attached to the pipe 40, and the pleat 43 is provided on the outer periphery of the pipe 40 between the preionized outer electrodes 42a and 42b (not shown).
As a result, a creeping distance between the preionized outer electrodes 42a and 42b can be secured, and an alternating oscillation operation can be realized.

The configuration of the single chamber excimer laser apparatus has been described above, but the present invention can also be applied to an amplification stage laser of a MOPO type or MOPA type double chamber system as shown in FIGS.
In FIG. 8, an oscillation stage laser 100 includes an oscillation stage chamber 10, an oscillation stage high voltage pulse generator 12, a band narrowing module (hereinafter referred to as LNM) 16 for narrowing the spectrum, a front mirror 17, Consists of.
When a high voltage pulse is applied to the electrodes 10a and 10b by a power source composed of a high voltage pulse generator 12 and a charger (not shown), discharge occurs between the electrodes 10a and 10b to form an excimer. And it resonates with the resonator comprised by LNM16 and the front mirror 17, and a laser beam is generated. The LNM 16 includes a magnifying prism and a grating (diffraction grating) which is a wavelength selection element, and narrows the spectral width of the laser light.

The laser light from the oscillation stage laser 100 is changed in beam direction by the high reflection mirror 21 and incident on the high reflection mirror 22, where the beam direction is changed and injected into the amplification stage laser 300. The amplification stage laser 300 includes a resonator including two pairs of electrodes 30a and 30b and 30c and 30d, a rear mirror 36, and a front mirror 37.
The two pairs of electrodes 30b and 30c and 30d are each provided with the preionization mechanism shown in the above-described embodiment, and the preionization mechanism ensures insulation by the structure as described above.
Then, a high voltage pulse is applied from the high voltage pulse generators 32 and 34 to discharge the two pairs of electrodes 30a and 30b and 30c and 30d alternately. As a result, an excimer is formed, and the injected laser light resonates with a resonator composed of the rear mirror 36 and the front mirror 37, and is amplified and emitted.

FIG. 9 shows an example of the configuration of a MOPA double chamber system. The oscillation stage laser 100 is the same as that shown in FIG. 8, and the oscillation stage chamber 10 and the oscillation stage high voltage are shown. The pulse generator 12, a band narrowing module (hereinafter referred to as LNM) 16 for narrowing the spectrum, and a front mirror 17 are configured.
When a high voltage pulse is applied to the electrodes 10a and 10b by a power source composed of a high voltage pulse generator 12 and a charger (not shown), a discharge occurs between the electrodes 10a and 10b, and laser light is generated. .

The laser light from the oscillation stage laser 100 is reflected by the high reflection mirrors 21 and 22 and injected into the high reflection amplification stage laser 301.
The amplification stage laser 301 has two pairs of electrodes 30a and 30b and 30c and 30d. Then, by applying a high voltage pulse from the high voltage pulse generators 32 and 34 and discharging the two pairs of electrodes 30a and 30b and 30c and 30d alternately, the laser light injected into the amplification stage laser 301 is amplified. Then exit.
As described above, the two pairs of electrodes 30a and 30b and 30c and 30d are each provided with a preionization mechanism, and the preionization mechanism has the structure as described in the above embodiment, ensuring insulation. Yes.

1 is a configuration diagram of a laser device according to a first embodiment of the present invention. It is a figure which shows the structural example of the preliminary ionization electrode which concerns on the 1st Embodiment of this invention. It is a figure which shows the structural example of the electric circuit of the chamber part of the laser apparatus which concerns on 1st Embodiment. It is a figure which shows another structural example of the preliminary ionization electrode which concerns on 1st Embodiment. It is a figure which shows the structural example of the preliminary ionization electrode which concerns on the 2nd Embodiment of this invention. It is a figure which shows the structural example of the electric circuit of the chamber part of the laser apparatus which concerns on 2nd Embodiment. It is a figure which shows another structural example of the preionization electrode which concerns on 2nd Embodiment. It is a figure which shows the structural example of the MOPO system double chamber laser system to which this invention is applied. It is a figure which shows the structural example of the MOPA system double chamber laser system to which this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Oscillation stage chamber 10a, 10b Electrode 12 Oscillation stage high voltage pulse generator 16 Narrow band module (LNM)
17 Front mirror 21, 22 High reflection mirror 30 Chamber 30a, 30b, 30c, 30d Electrode 33, 34 High voltage pulse generator 36 Rear mirror 37 Front mirror 39 Insulating material (alumina ceramic)
40, 40a, 40b Alumina ceramic pipe 40c Sealing portion 41a, 41b Pre-ionization inner electrode 42a, 42b Pre-ionization outer electrode 43 Fold 51 Cross flow fan 52 Heat exchanger 53, 54 Guide 60, 61, 62 Creeping surface 100 For oscillation stage Laser 300 Laser for amplification stage (MOPO method)
301 Laser for amplification stage (MOPA method)

Claims (5)

A laser chamber in which a laser gas is sealed; a plurality of electrode pairs that are arranged along the optical path of the laser beam inside the laser chamber and are opposed to each other with a predetermined spacing; and discharge the electrode pairs. Power supply circuit for
A high-repetition high-power pulse gas laser device that sequentially applies a pulsed voltage from the power supply circuit to the plurality of electrode pairs, and sequentially generates discharge at a predetermined time interval between the plurality of electrode pairs,
A cylindrical insulator including a cylindrical portion that is disposed adjacent to one electrode of each electrode pair and has a hollow inside, a preionization inner electrode disposed in an inner layer of the cylindrical portion, and the cylinder and a outer layer arranged preionization outside electrode parts, and preionization mechanism for generating a corona discharge by a voltage being applied between the preionization inside electrode and the preionization outer electrode,
An insulating material interposed between the preionization inner electrodes or the preionization outer electrodes to which a high-voltage side voltage in an adjacent preionization mechanism is applied; and
With
The pre-ionization inner electrode is formed of a plate-shaped conductor, and a high-repetition and high-power pulse gas laser device characterized in that Each preionization mechanism is disposed adjacent to the ground potential electrode in each electrode pair,
In each preionization mechanism, the preionization outer electrode is set to the ground side potential, and a high voltage is applied to the preionization inner electrode ,
The cylindrical insulator includes an insulator disposed in a portion facing another adjacent cylindrical insulator, and is divided and arranged for each preliminary ionization mechanism so as to be separated between adjacent preliminary ionization mechanisms. The high-repetition high-power pulse gas laser device according to claim 1, wherein Each preionization mechanism is disposed adjacent to the ground potential electrode in each electrode pair,
In each preionization mechanism, the preionization outer electrode is set to the ground side potential, and a high voltage is applied to the preionization inner electrode ,
The cylindrical insulator includes an insulator disposed between the preliminary ionization inner electrodes between adjacent preliminary ionization mechanisms, and is connected between the adjacent preliminary ionization mechanisms. 1. A high repetition high power pulse gas laser device according to 1. Each preionization mechanism is arranged adjacent to the high-potential-side electrode in each electrode pair,
In each preionization mechanism, the preionization inner electrode is set to the ground side potential, and a high voltage is applied to the preionization outer electrode ,
The cylindrical insulator includes an insulator disposed in a portion facing another adjacent cylindrical insulator, and is divided and arranged for each preliminary ionization mechanism so as to be separated between adjacent preliminary ionization mechanisms. The high-repetition high-power pulse gas laser device according to claim 1, wherein Each preionization mechanism is arranged adjacent to the high-potential-side electrode in each electrode pair,
In each preionization mechanism, the preionization inner electrode is set to the ground side potential, and a high voltage is applied to the preionization outer electrode ,
The insulator of the cylindrical portion includes an insulating fold disposed between the pre-ionization outer electrodes between adjacent pre-ionization mechanisms, and is connected between the pre-ionization mechanisms adjacent to each other. The high-repetition high-power pulse gas laser device according to claim 1.

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