Dust removal device for working gas of high-power excimer laser

Abstract

The utility model discloses a dust removal device for working gas of a high-power excimer laser, which comprises a closed dust remover shell, and one end of the dust remover shell is provided with a gas inlet pipe which is communicated with a resonant cavity of the excimer laser so as to enable the working gas in the resonant cavity to enter the dust remover shell. A discharge dust collection electrode capable of performing high-voltage negative pulse discharge is arranged in the dust remover shell, and a gas feeding pipe capable of feeding gas purified by the discharge dust collection electrode into a resonant cavity of the excimer laser is arranged at the other end of the dust remover shell; the dust removal device for the working gas of the high-power excimer laser further comprises a high-voltage pulse power supply for supplying power to the discharge dust collection electrode and a gas circulation part for exhausting gas from the gas inlet pipe and supplying gas from the gas supply pipe. According to the utility model, the working gas in the resonator of the excimer laser is purified, the pollutant removal effect is good, the service life of the excimer laser can be prolonged, and the laser performance can be ensured.

Description

Technical Field

[0001] This utility model relates to the field of high-power excimer laser technology, and more specifically to a dust removal device for the working gas of a high-power excimer laser. Background Technology

[0002] Excimer lasers are the highest-power laser devices in the ultraviolet band. Their short wavelength and high power characteristics have led to their widespread application in industry, scientific research, and medicine. In recent years, with advancements in materials technology, optical processing technology, and high-voltage fast discharge technology, excimer lasers have continued to develop towards higher frequencies and higher power. High-power excimer lasers (>100W) have become the core light source for key equipment in some manufacturing industries. During discharge excitation, the high peak current combined with the chemically corrosive halogen gas in the gas mixture causes corrosion of the metal electrodes, generating a large amount of electrode sputtering particles, metal halide vapors, and other discharge contaminants in the discharge region. A gas purification system is needed to continuously purify the working gas to remove as many contaminants as possible, maintain the cleanliness of the working gas in the discharge region, ensure discharge quality, and reduce contamination of internal components such as the laser cavity. Therefore, the working gas purification system is crucial for improving the working gas lifetime and the overall lifetime of the discharge cavity in high-power excimer lasers. The efficiency of the working gas purification directly affects the laser gas lifetime and the overall lifetime of the laser discharge cavity. Traditional working gas purification systems use filtration, but their effectiveness in removing contaminants is limited, leading to a gradual decline in laser performance.

[0003] Therefore, this utility model was created based on the above-mentioned shortcomings. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a dust removal device for the working gas of high-power excimer lasers. This dust removal device effectively purifies the working gas within the resonator of the excimer laser, significantly reducing contaminants, thus extending the lifespan of the excimer laser and ensuring its laser performance.

[0005] This utility model is achieved through the following technical solution:

[0006] A dust removal device for the working gas of a high-power excimer laser includes a sealed dust collector housing. One end of the dust collector housing is provided with an inlet pipe that communicates with the resonant cavity of the excimer laser to allow the working gas in the resonant cavity to enter the dust collector housing. Inside the dust collector housing is a discharge dust collection electrode capable of high-voltage negative pulse discharge. The other end of the dust collector housing is provided with a gas delivery pipe that delivers the gas purified by the discharge dust collection electrode into the resonant cavity of the excimer laser. The dust removal device for the working gas of a high-power excimer laser also includes a high-voltage pulse power supply for powering the discharge dust collection electrode and a gas circulation component for drawing gas from the inlet pipe and delivering gas from the gas delivery pipe.

[0007] The discharge dust collection electrode includes multiple spaced metal shunts inside the dust collector housing that allow working gas from the inlet pipe to enter. A conductive metal wire extends along the axis of each metal shunt. The metal shunt is grounded, and the conductive metal wire is connected to a high-voltage negative electrode potential.

[0008] The aforementioned metal manifold is a stainless steel metal manifold.

[0009] The discharge dust collection electrode adopts a bipolar pulse drive mode, with negative pulses accounting for >95%.

[0010] The high-voltage pulse power supply includes an integrated energy storage capacitor, a high-voltage power supply module, and a fast switching device. It provides a peak voltage amplitude of 2.5±0.2kV, a pulse waveform characteristic of Gaussian envelope, a pulse width of less than 400 nanoseconds, a fall time of less than 50 nanoseconds, and a pulse repetition frequency of 5kHz to 25kHz.

[0011] The excimer laser includes a housing capable of being filled with working gas, an electrode assembly arranged along its length to discharge and excite the working gas to generate an excimer laser, a total reflection mirror at one end of the housing, and a transmission coupling mirror at the other end of the housing for the excimer laser to be emitted.

[0012] The electrode assembly includes a pair of parallel elongated electrodes, and a pre-ionizer is also provided inside the housing.

[0013] The outlet of the air supply pipe is located at the end of the housing, and the inlet of the air inlet pipe is located in the middle of the housing.

[0014] The air inlet of the air inlet pipe faces the end of the housing so that the air intake direction is along the length of the housing.

[0015] Compared with the prior art, the present invention has the following advantages:

[0016] 1. During operation, the discharge collecting electrode inside the dust collector housing undergoes continuous high-voltage negative pulse discharge, forming a periodic electric field. The working gas containing solid particulate pollutants and metal halide components, etc., within the resonant cavity of the excimer laser, is drawn into the dust collector housing through a gas circulation component and passes through the aforementioned electric field. The metal halide components undergo pyrolysis at the gaps between the discharge collecting electrodes. The metal particles and halogen free radicals generated by their decomposition form an electrophoretic deposition phenomenon under the action of a high-voltage electrostatic field, ultimately achieving electrostatic deposition of metal halide components and electric field capture of particulate pollutants. The purified gas then returns to the resonant cavity through a gas supply pipe. Using a discharge collecting electrode to perform continuous high-voltage negative pulse discharge to purify the working gas effectively removes pollutants, extends the lifespan of the excimer laser, and ensures laser performance.

[0017] 2. The discharge dust collection electrode of this utility model includes multiple metal shunts spaced apart inside the dust collector housing, which allow the working gas in the inlet pipe to enter. Conductive metal wires extend along the axial direction inside the metal shunts. The metal shunts are grounded, and the conductive metal wires are connected to a high-voltage negative electrode potential. Therefore, when a high-voltage pulse is applied to the discharge dust collection electrode, a pulse corona discharge is generated, forming a periodic electric field. This causes the working gas flowing through the discharge dust collection electrode to undergo multiple high-frequency ionization and breakdown phenomena, thereby achieving dust removal from the working gas. Solid pollutants are deposited on the metal shunts. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the present invention;

[0019] Figure 2 This is a schematic diagram of the discharge dust collection electrode of this utility model;

[0020] Figure 3 It is one of the waveforms displayed on an oscilloscope of the high-voltage pulse applied to the discharge dust collection electrode and the corresponding high-voltage pulse.

[0021] Figure 4 The second image shows the high-voltage pulse applied to the discharge dust collection electrode and the corresponding waveform displayed on the oscilloscope.

[0022] Figure 5 The third image shows the high-voltage pulse applied to the discharge dust collection electrode and the corresponding waveform displayed on the oscilloscope. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings:

[0024] like Figure 1 and Figure 2As shown, a dust removal device for the working gas of a high-power excimer laser includes a sealed dust collector housing 1. One end of the dust collector housing 1 has an inlet pipe 4, which is connected to the resonant cavity 3 of the excimer laser 2. The inlet pipe 4 allows the working gas containing solid particulate contaminants and metal halide components, among other impurities, from the resonant cavity 3 into the dust collector housing 1. Inside the dust collector housing 1 is a discharge dust collection electrode 5 capable of high-voltage negative pulse discharge. The discharge dust collection electrode 5 continuously discharges with high-voltage negative pulses, forming a periodic electric field. The working gas entering the dust collector housing 1 from the inlet pipe 4 passes through this electric field, causing the metal halide components to be discharged... A pyrolysis reaction occurs in the gap between the electrostatic precipitator electrode 5. The metal particles and halogen free radicals produced by its decomposition form an electrophoretic deposition phenomenon under the action of a high-voltage electrostatic field. Ultimately, the electrostatic deposition of metal halide components and the electric field capture of particulate pollutants are achieved. At this time, the working gas is purified by removing pollutants. The purified working gas is then sent into the resonant cavity 3 of the excimer laser 2 from the gas supply pipe 6 at the other end of the dust collector shell 1, thereby achieving uninterrupted purification and dust removal of the working gas. The high-voltage negative pulse continuous discharge of the electrostatic precipitator electrode 5 is used to purify the working gas, which has a good effect on removing pollutants, can extend the service life of the excimer laser and ensure laser performance.

[0025] like Figure 1 As shown, the dust removal device for the working gas of a high-power excimer laser also includes a high-voltage pulse power supply 7 for powering the discharge dust collection electrode 5, and a gas circulation component (not shown in the figure) for drawing gas from the inlet pipe 4 and sending gas from the outlet pipe 6.

[0026] The high-voltage pulse power supply 7 includes an integrated energy storage capacitor, a high-voltage power supply module, and a fast switching device. Combined with a pulse shaping network (including passive components and a pulse transformer), it utilizes solid-state converter devices such as thyristors and IGBTs to achieve controllable energy release and waveform modulation, providing high-voltage repetitive pulse discharge for the dust removal device. In this embodiment, the peak voltage amplitude provided by the high-voltage pulse power supply 7 is 2.5±0.2kV, the pulse waveform is characterized by a Gaussian envelope, the pulse width is less than 400 nanoseconds, the fall time is less than 50 nanoseconds, and the pulse repetition frequency is 5kHz to 25kHz.

[0027] like Figure 1 and Figure 2As shown, the discharge dust collection electrode 5 includes multiple spaced metal diverter pipes 51 located inside the dust collector housing 1, allowing the working gas from the inlet pipe 4 to enter. Conductive metal wires 52 extend along the axial direction of each metal diverter pipe 51. The metal diverter pipes 51 are grounded, and the conductive metal wires 52 are connected to a high-voltage negative electrode potential. The metal diverter pipes 51 are made of stainless steel. Therefore, when a high-voltage pulse is applied to the discharge dust collection electrode 5, a pulsed corona discharge is generated, forming a periodic electric field. This causes the working gas flowing through the discharge dust collection electrode 5 to undergo multiple high-frequency ionization breakdowns, thereby achieving dust removal from the working gas. Solid pollutants are deposited on the metal diverter pipes 51. The gas circulation component can draw the working gas containing pollutants to the electric field of the stainless steel metal diverter pipes 51 at a stable flow rate and direction, optimizing the airflow path and avoiding local eddies or uneven concentration that could affect the dust removal effect.

[0028] The discharge dust collection electrode 5 adopts a bipolar pulse drive mode, with negative pulses accounting for >95% to ensure dust removal effect.

[0029] like Figure 1 As shown, the excimer laser 2 includes a housing 21 capable of being filled with a working gas. The working gas consists of a halogen gas (Cl2 / F2), a heavy inert gas (Ar / Kr / Xe), and a light inert carrier gas (He / Ne), and its pressure is maintained above 1.5 bar (preferably in the 3.5-7 bar range). An electrode assembly 22 is provided along the length of the housing 21 to discharge and excite the working gas to generate an excimer laser. The electrode assembly 22 includes a pair of parallel elongated electrodes 221. A plasma channel is formed between the elongated electrodes 221 by a high-voltage short pulse to excite the excimer state (such as XeCl / ArF) and achieve optical gain. A pre-ionizer 222 is also provided within the housing 21 to ensure discharge stability. A total reflection mirror 23 is provided at one end of the housing 21, and a transmission coupling mirror 24 for the excimer laser to be emitted is provided at the other end. The laser pulse along... Figure 1 It shoots out in the direction of the middle arrow F.

[0030] like Figure 1 As shown, the outlet of the gas supply pipe 6 is located at the end of the housing 21, and the inlet of the gas inlet pipe 4 is located in the middle of the housing 21. The inlet of the gas inlet pipe 4 faces the end of the housing 21 so that the air intake direction is along the length of the housing 21 to ensure smooth airflow. In this embodiment, each excimer laser is equipped with two sets of the aforementioned dust removal devices to improve the purification and dust removal efficiency of the working gas in the resonant cavity 3.

[0031] The present invention has been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the invention.

Claims

1. A dust removal device for the working gas of a high-power excimer laser, characterized in that: The device includes a sealed dust collector housing (1), one end of which is provided with an air inlet pipe (4) that communicates with the resonant cavity (3) of the excimer laser (2) so that the working gas in the resonant cavity (3) enters the dust collector housing (1). The dust collector housing (1) is provided with a discharge dust collection electrode (5) capable of high-voltage negative pulse discharge, and the other end of the dust collector housing (1) is provided with a gas supply pipe (6) that can send the gas purified by the discharge dust collection electrode (5) into the resonant cavity (3) of the excimer laser (2). The dust removal device for the working gas of the high-power excimer laser also includes a high-voltage pulse power supply (7) for powering the discharge dust collection electrode (5) and a gas circulation component for drawing gas from the air inlet pipe (4) and sending gas from the gas supply pipe (6).

2. The dust removal device for the working gas of a high-power excimer laser according to claim 1, characterized in that: The discharge dust collection electrode (5) includes multiple metal shunt pipes (51) arranged inside the dust collector housing (1) that are spaced apart and allow working gas from the inlet pipe (4) to enter. A conductive metal wire (52) extends along the axial direction inside the metal shunt pipe (51). The metal shunt pipe (51) is grounded, and the conductive metal wire (52) is connected to a high voltage negative electrode potential.

3. The dust removal device for the working gas of a high-power excimer laser according to claim 2, characterized in that: The metal manifold (51) is a stainless steel metal manifold.

4. The dust removal device for the working gas of a high-power excimer laser according to claim 2, characterized in that: The discharge dust collection electrode (5) adopts a bipolar pulse drive mode, with negative pulses accounting for >95%.

5. The dust removal device for the working gas of a high-power excimer laser according to claim 4, characterized in that: The high-voltage pulse power supply (7) includes an integrated energy storage capacitor, a high-voltage power supply module and a fast switching device. The peak voltage amplitude provided is 2.5±0.2kV, the pulse waveform is a Gaussian envelope, the pulse width is less than 400 nanoseconds, the fall time is less than 50 nanoseconds, and the pulse repetition frequency is 5kHz to 25kHz.

6. The dust removal device for the working gas of a high-power excimer laser according to claim 4, characterized in that: The excimer laser (2) includes a housing (21) capable of being filled with working gas. An electrode assembly (22) is provided inside the housing (21) along its length direction to discharge and excite the working gas inside to generate an excimer laser. A total reflection mirror (23) is provided at one end of the housing (21), and a transmission coupling mirror (24) for the excimer laser to be emitted is provided at the other end of the housing (21).

7. The dust removal device for the working gas of a high-power excimer laser according to claim 6, characterized in that: The electrode assembly (22) includes a pair of parallel elongated electrodes (221), and the housing (21) is also provided with a pre-ionizer (222).

8. The dust removal device for the working gas of a high-power excimer laser according to claim 6, characterized in that: The outlet of the air supply pipe (6) is located at the end of the housing (21), and the air inlet of the air inlet pipe (4) is located in the middle of the housing (21).

9. The dust removal device for the working gas of a high-power excimer laser according to claim 7, characterized in that: The air inlet of the air inlet pipe (4) faces the end of the housing (21) so that the air intake direction is along the length direction of the housing (21).

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