A dust removal device for the working gas of a laser resonator and an excimer laser

Abstract

The present application provides a dust removal device for the working gas of a laser resonator, comprising: a cooling chamber at least connected to the laser resonator and including an air inlet and an air outlet; the cooling chamber includes a plurality of air flow channels connecting the air inlet and the air outlet; when the gas to be cooled passes through the air flow channels, heat exchange occurs by contacting the walls of the air flow channels, so that the temperature of the gas to be cooled decreases. In the above device, the cooling chamber is provided to reduce the temperature of the gas to be cooled. As the gas temperature decreases, the kinetic energy of the gas molecules decreases, so that the dust particles in the gas are subjected to molecular collisions and their kinetic energy decreases. Therefore, the dust particles are separated from the gas due to the action of gravity and fall on the pore walls of the air flow channels. Therefore, the removal efficiency of the dust particles in the gas is improved.

Description

Technical Field

[0001] The present application relates to the technical field of excimer lasers, and particularly to a dust removal device for the working gas of a laser resonator, and an excimer laser. Background Art

[0002] In the field of high-end lithography, the laser of an excimer laser has the characteristics of high repetition rate, narrow line width and large energy. Therefore, the laser of an excimer laser is a dominant light source in the application of semiconductor lithography.

[0003] In practical applications, the gas inside the discharge cavity of an excimer laser has the following problems. One is that the gas is corrosive, and the other is the high-repetition-rate high-voltage discharge and high-temperature environment, resulting in a large amount of discharge dust in the gas inside the discharge cavity. However, the discharge dust will contaminate the lens, leading to problems such as thermal stress concentration and optical performance degradation of the lens.

[0004] In the prior art, to solve the above technical problems, an electrostatic precipitator is usually used to clean the gas, and then the clean gas is returned to the discharge cavity. The structural diagram of the electrostatic precipitator in the prior art is as Figure 1 shown. It adopts a wire-tube structure. By applying a negative high voltage to the thin wire in the pipeline, the dust in the gas is charged and the dust drifts on the pipe wall to remove the dust in the gas.

[0005] However, since the dust in the excimer laser includes metal fluorides and pure metal particles, and the metal particles have good electrical conductivity. Therefore, the method of using an electrostatic precipitator to remove gas dust in the prior art has the problem of low dust particle removal efficiency. Summary of the Invention

[0006] The present application provides a dust removal device for the working gas of a laser resonator to solve the problem of low dust particle removal efficiency in the method of using an electrostatic precipitator to remove gas dust in the prior art. The present application also provides an excimer laser.

[0007] The present application provides a dust removal device for the working gas of a laser resonator, including: a cooling chamber at least connected to the laser resonator, including an air inlet and an air outlet; the cooling chamber includes a plurality of air flow channels connecting the air inlet and the air outlet; when the gas to be cooled passes through the air flow channels, it exchanges heat with the air flow channel walls, so that the temperature of the gas to be cooled decreases.

[0008] Optionally, it further includes: a flow equalizing plate connected to the air inlet of the cooling chamber; the flow equalizing plate includes a plurality of flow equalizing holes including an air inlet and an air outlet; the gas to be cooled enters the air inlet of the cooling chamber through the flow equalizing holes.

[0009] Optionally, the flow equalizing plate includes at least one row of flow equalizing holes, a plurality of flow equalizing holes are arranged at equal intervals in the at least one row of flow equalizing holes, and at least one flow equalizing hole in the at least one row of flow equalizing holes communicates with at least one air flow channel of the cooling chamber.

[0010] Optionally, the cooling chamber includes a multi-stage cooling chamber with at least two stages.

[0011] Optionally, the multi-stage cooling chamber with at least two stages includes a first-stage cooling chamber and a second-stage cooling chamber; the first-stage cooling chamber includes a hole array evenly distributed, and each through hole in the hole array is a first-stage air flow channel; the second-stage cooling chamber includes at least one umbrella-shaped structure arranged coaxially, the umbrella-shaped structure includes at least one ring, and the gap between adjacent rings is a second-stage air flow channel; the gas to be cooled undergoes a first cooling process through the first-stage air flow channel and then undergoes a second cooling process through the second-stage air flow channel.

[0012] Optionally, the cooling chamber is arranged in a symmetric structure, and one side of the symmetric two sides of the cooling chamber respectively includes a flow equalizing plate, the first-stage cooling chamber and the second-stage cooling chamber; the gas to be cooled enters the first-stage cooling chamber through the flow equalizing plates on the symmetric two sides respectively, and then enters the second-stage cooling chamber.

[0013] Optionally, the second-stage air flow channel is longer than the first-stage air flow channel.

[0014] Optionally, it further includes: an electrostatic dust removal chamber communicated with the cooling chamber, and the electrostatic dust removal chamber is arranged in series with the cooling chamber; the electrostatic dust removal chamber includes a dust removal pipe and a high-voltage electrode arranged at the central position of the dust removal pipe, and an electric field intersecting the air flow direction is formed between the high-voltage electrode and the pipe wall of the dust removal pipe when the high-voltage electrode is energized.

[0015] This application also provides an excimer laser, including: the dust removal device for the working gas of the laser resonator described above.

[0016] Compared with the prior art, the dust removal device for the working gas of the laser resonator of this application includes: a cooling chamber at least connected to the laser resonator, including an air inlet and an air outlet; the cooling chamber includes a plurality of air flow channels connecting the air inlet and the air outlet; when the gas to be cooled passes through the air flow channels, heat exchange occurs when it contacts the wall of the air flow channels, so that the temperature of the gas to be cooled decreases.

[0017] In the above device, a cooling chamber is provided to lower the temperature of the gas to be cooled. As the gas temperature decreases, the kinetic energy of gas molecules decreases, causing the dust particles in the gas to reduce their kinetic energy due to molecular collisions. Therefore, the dust particles separate from the gas under the action of gravity and fall onto the pore wall of the gas flow channel. As a result, the removal efficiency of dust particles in the gas is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. 6 is a schematic structural diagram of an electrostatic dust removal structure provided by the prior art.

[0019] Figure 2 FIG. Figure 1 is a side view of

[0020] Figure 3 FIG. 16 is a first schematic structural diagram of a dust removal device for the working gas of a laser resonator according to an embodiment of the present application.

[0021] Figure 4 FIG. Figure 3 is a cross-sectional view of

[0022] Figure 5 FIG. Figure 3 is a schematic structural diagram of the first-stage cooling chamber of

[0023] Figure 6 FIG. Figure 3 is a schematic structural diagram of the second-stage cooling chamber of

[0024] Figure 7 FIG. Figure 6 is a sectional view of

[0025] Figure 8 FIG. 44 is a second schematic structural diagram of a dust removal device for the working gas of a laser resonator according to an embodiment of the present application.

[0026] Figure 9 FIG. Figure 8 is a sectional view of

[0027] Among them, the first-stage cooling chamber 101, the first contact surface 101-1, the second contact surface 101-2, the pore array 101-3; the second-stage cooling chamber 102, the pore 102-1, at least one coaxial umbrella-shaped structure 102-2, the flow equalizing plate 103, the cooling chamber 100, the electrostatic dust removal chamber 200, the dust removal pipe 201, the high-voltage electrode 202. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the connotation of the present application. Therefore, the present application is not limited by the specific implementations disclosed below.

[0029] The present application provides a dust removal device for the working gas of a laser resonator to solve the problem of low dust particle removal efficiency in the prior art when using an electrostatic precipitator to remove gas dust.

[0030] The electrostatic precipitator used in the prior art is as Figure 1 and Figure 2 shown. Figure 1 FIG. Figure 2 is Figure 1 a schematic structural diagram of the electrostatic dust removal structure provided by the prior art, Figure 1 and Figure 2 is a side view of

[0031] As shown in

[0032] and

[0033] The electrostatic precipitator of the prior art includes a plurality of electrostatic dust removal tubes 10 and thin wires 11 passing through the electrostatic dust removal tubes. During operation, voltages with opposite electrode polarities are applied to the electrostatic dust removal tubes and the thin wires. On the one hand, a stable corona region is formed near the thin wires for discharging, so that the dust particles in the gas 12 entering the electrostatic dust removal tubes carry charges; on the other hand, under the action of the electric field formed between the thin wires and the inner wall of the electrostatic dust removal tubes, the charged dust particles will migrate to the surface of the thin wires or the inner wall of the electrostatic dust removal tubes to remove the dust particles in the gas.

[0034] However, since the dust in the excimer laser includes metal fluorides and metal particles, and the metal particles have good electrical conductivity. Therefore, the prior art method of using an electrostatic precipitator to remove gas dust has the problem of low dust particle removal efficiency.

[0035] To solve the problem of low efficiency of removing dust particles in the gas by the electrostatic precipitator in the above prior art, the present application proposes a dust removal device for the working gas of a laser resonator. Figure 3 Please refer to Figure 3The first structural schematic diagram of a dust removal device for the working gas of a laser resonator provided by an embodiment of the present application.

[0036] The dust removal device includes a flow equalizing plate 103 and a cooling chamber.

[0037] The flow equalizing plate 103 is used for gas shunting. After the gas is shunted through the flow equalizing holes on the flow equalizing plate, it is introduced into the cooling chamber, so as to enhance the effect of reducing the temperature of the gas in the cooling chamber.

[0038] Specifically, the flow equalizing plate includes at least one row of flow equalizing holes. A plurality of evenly spaced flow equalizing holes are arranged in at least one row of flow equalizing holes, and at least one flow equalizing hole in at least one row of flow equalizing holes is communicated with at least one air flow channel of the cooling chamber.

[0039] The cooling chamber is used for cooling the gas. By reducing the temperature of the gas, the dust particles in the gas are separated from the gas, and the dust particles fall into the air flow channel of the cooling chamber due to gravity.

[0040] The cooling chamber includes a multi-stage cooling chamber with at least two stages, such as Figure 3 shown, the multi-stage cooling chamber with at least two stages includes a first-stage cooling chamber 101 and a second-stage cooling chamber 102.

[0041] The first-stage cooling chamber 101 is used to form a first-stage cooling area and perform the first cooling treatment on the air flow.

[0042] Please refer to Figure 4 , Figure 4 which is Figure 3 the sectional view of. As Figure 4 shown, the first-stage cooling chamber 101 includes a first contact surface 101-1, a second contact surface 101-2, and a uniformly distributed hole array 101-3. Each through hole in the hole array is a first-stage air flow channel.

[0043] The hole array 101-3 penetrates through the first contact surface 101-1 and the second contact surface 101-2. As Figure 3 shown, the body of the first-stage cooling chamber 101 is a cylindrical body, and a uniformly distributed hole array is penetrated and arranged on the first contact surface and the second contact surface of the cylindrical body, such as Figure 4 and Figure 5 shown for the hole array and the first contact surface. Figure 5 which is Figure 3 the structural schematic diagram of the first-stage cooling chamber.

[0044] After being powered on, the first-stage cooling chamber is cooled down. Each cooling through-hole in the hole array is in a low-temperature environment, providing a first-stage air flow channel for the gas to be cooled down to reduce its temperature. When the gas to be cooled down passes through each cooling through-hole in the hole array, the gas temperature decreases, the kinetic energy of gas molecules decreases, and the dust particles in the gas move and collide, and then fall onto the hole wall of the cooling through-hole due to gravity and separate from the gas, thereby achieving the effect of removing larger dust particles in the gas.

[0045] In Figure 3 and Figure 4 the body of the first-stage cooling chamber is a cylindrical body. In addition, the body can also be a rectangular body or a body of other shapes, which is not limited herein.

[0046] As Figure 3 shown, the second-stage cooling chamber 102 is used to form a second cooling area for performing a second cooling process on the gas flow that has been cooled down by the first-stage cooling chamber 101.

[0047] The second-stage cooling chamber 102 includes at least one umbrella structure arranged coaxially. The umbrella structure includes at least one ring, and the gap between adjacent rings is the second-stage air flow channel.

[0048] From Figure 3 , Figure 6 and Figure 7 it can be seen that Figure 6 is Figure 3 the structural schematic diagram of the second-stage cooling chamber. Figure 7 is Figure 6 the sectional view.

[0049] The second-stage cooling chamber 102 includes a hole 102-1 and at least one umbrella structure 102-2 arranged coaxially.

[0050] From Figure 6 and Figure 7 it can be seen that the hole 102-1 is a round hole located at the axial center position, and at least one umbrella structure 102-2 is arranged coaxially. From Figure 7 it can be seen that a plurality of umbrella structures are stacked in sequence along the axial direction of the cylinder on the inner side of the second-stage cooling chamber, and there is a gap between adjacent umbrella structures. Among them, each umbrella structure 102-2 includes rings with different diameters nested outside the round hole in sequence and having an inclination angle with the horizontal direction, and there is a gap between each ring.

[0051] Therefore, the second-stage air flow channel in the second-stage cooling chamber 102 includes the internal channel of the hole 102-1, the gap between adjacent umbrella structures, and the gap between adjacent rings of each adjacent umbrella structure.

[0052] After being powered on, the second-stage cooling chamber 102 is subjected to a second temperature reduction treatment. The hole 102-1 and at least one umbrella structure 102-2 are subjected to the temperature reduction treatment. The internal channel of the hole 102-1, the gaps between adjacent umbrella structures, and the gaps between adjacent rings of each adjacent umbrella structure form a second-stage low-temperature gas flow channel. The gas to be cooled is introduced from the first-stage cooling chamber into the second-stage cooling chamber, and the temperature of the gas is further reduced. The dust particles in the gas are subjected to a second temperature reduction. For relatively large metal dust particles, the collision motion is further reduced due to the temperature reduction, and the dust particles fall on the hole wall or the umbrella wall due to their own gravity, thereby further removing the dust particles in the gas.

[0053] As Figure 3 shown, the second-stage gas flow channel of the second-stage cooling chamber is longer than the first-stage gas flow channel of the first-stage cooling chamber, which increases the temperature reduction process of the gas to be cooled, enables the gas to be fully temperature-reduced, and increases the removal efficiency of the dust particles in the gas.

[0054] The above is the structural diagram of the first dust removal device for the working gas of the laser resonator provided by the present application.

[0055] In the above device, the dust particles in the gas are removed by means of temperature reduction treatment. Specifically, the first temperature reduction is carried out through the first-stage cooling chamber, and the second temperature reduction is carried out through the second-stage cooling chamber. The first temperature reduction and the second temperature reduction reduce the temperature of the gas and the kinetic energy of the gas molecules, and further cause the dust particles to reduce their motion energy due to molecular collisions. Therefore, the dust particles are separated from the gas due to gravity and fall on the hole walls of the first-stage gas flow channel and the second-stage gas flow channel. Therefore, the efficiency of removing the dust particles in the gas is improved.

[0056] In addition, in order to further increase the removal efficiency of the dust particles in the gas, the present application also provides a second dust removal device for the working gas of the laser resonator. As Figure 8 and Figure 9 shown, an electrostatic dust removal chamber 200 is connected to the cooling chamber 100.

[0057] Please refer to Figure 8 , Figure 8 which is the second structural schematic diagram of a dust removal device for the working gas of the laser resonator provided by an embodiment of the present application.

[0058] As Figure 8 shown, the dust removal device includes a cooling chamber 100 and an electrostatic dust removal chamber 200. The electrostatic dust removal chamber 200 is connected in series with and communicated with the cooling chamber 100, that is, the working gas can flow through the electrostatic dust removal chamber 200 and the cooling chamber 100 in sequence or flow through the cooling chamber 100 and the electrostatic dust removal chamber 200 in sequence.

[0059] In Figure 8 only the second-stage cooling chamber shown in Figure 3 is shown for the structure of the cooling chamber 100. In actual applications, the cooling chamber 100 of the dust removal device with the electrostatic dust removal chamber 200 can be a combination of two-stage cooling chambers or any one of the above two-stage cooling chambers.

[0060] The structural diagram of the cooling chamber 100 is as Figure 9 shown above. Figure 9 It is Figure 8 a sectional view of. The electrostatic dust removal chamber 200 includes a plurality of dust removal tubes 201 and a high-voltage electrode 202 disposed at the central position of each of the plurality of dust removal tubes. When the high-voltage electrode is energized, an electric field intersecting the gas flow direction is formed with the tube wall of the dust removal tube.

[0061] The electrostatic dust removal chamber 200 is used for electrostatic dust removal of the gas that has been cooled through the cooling chamber 100. Specifically, an electric field is formed inside the electrostatic dust removal chamber 200, and the dust particles carrying charges in the gas migrate to the tube wall of the dust removal tube 201 of the electrostatic dust removal device under the action of the electric field to remove the dust particles in the gas.

[0062] Please refer to Figure 9 , the dust removal tube 201 is a cylindrical hollow tube, and the high-voltage electrode 202 is located at the axial center of the tube body.

[0063] Among them, the high-voltage electrode is used to apply a voltage when energized, so that a corona environment is generated around the high-voltage electrode to generate local discharge to charge the dust particles in the gas. The high-voltage electrode can be a metal wire.

[0064] In addition, a voltage opposite to the electrode polarity of the high-voltage electrode is applied to the tube wall of the dust removal tube, so that an electric field is formed between the high-voltage electrode and the tube wall, and the charged dust particles in the gas migrate to the surface of the high-voltage electrode or the tube wall surface of the dust removal tube due to the action of the electric field.

[0065] Specifically, the voltage type of the high-voltage electrode is the first voltage, and the voltage type of the tube wall of the dust removal tube is the second voltage with the opposite voltage polarity to the first voltage; the gas flow direction is along the direction of the tube wall or the high-voltage electrode of the dust removal tube; the direction of the electric field formed between the tube wall of the tube wall and the high-voltage electrode is the axial diameter direction of the cylinder perpendicular to the tube wall.

[0066] For example, a positive voltage is applied to the high-voltage electrode, and a negative voltage or zero voltage is applied to the wall of the dust removal tube. First, a corona region is generated near the high-voltage electrode, and the discharge charges generated in the corona region are carried by the dust particles in the gas. Then, the electric field formed between the high-voltage electrode and the wall of the tube migrates the charged dust particles to the surface of the high-voltage electrode or the wall of the tube. Specifically, the direction of the electric field formed between the high-voltage electrode and the wall of the tube is from the high-voltage electrode to the wall of the tube. Correspondingly, the dust particles carrying positive charges migrate to the surface of the wall of the tube, and the dust particles carrying negative charges migrate to the surface of the high-voltage electrode.

[0067] Again, for example, a negative voltage is applied to the high-voltage electrode, and a positive voltage or zero voltage is applied to the wall of the dust removal tube. First, a corona region is generated near the high-voltage electrode, and the discharge charges generated in the corona region are carried by the dust particles in the gas. Then, the electric field formed between the high-voltage electrode and the wall of the tube migrates the charged dust particles to the surface of the high-voltage electrode or the wall of the tube. Specifically, the direction of the electric field formed between the high-voltage electrode and the wall of the tube is from the wall of the tube to the high-voltage electrode. Correspondingly, the dust particles carrying positive charges migrate to the surface of the high-voltage electrode, and the dust particles carrying negative charges migrate to the surface of the wall of the tube.

[0068] For the second dust removal device for the working gas of the laser resonator described above, first, the two-pole cooling chamber that cools the dust removal chamber cools the relatively large metal dust particles by reducing the temperature, thereby reducing the kinetic energy of the movement of the dust particles. After colliding and moving, due to their own gravity, they fall on the wall surface of the cooling chamber, thus removing the relatively large dust particles in the gas. Then, through the method of electrostatic dust removal, the dust particles are charged, and the charged dust particles are migrated to the surface of the electrostatic dust removal chamber by the action of the electric field, further removing the dust particles in the gas. By using the two methods of low-temperature dust removal and electrostatic dust removal, the removal efficiency of the dust particles in the gas is improved.

[0069] The present application also provides an excimer laser that uses the above-mentioned dust removal device for the working gas of the laser resonator.

[0070] Application Scenario 1

[0071] In practical applications, the gas containing dust particles in the discharge cavity of an excimer laser enters the flow equalizing plate from the discharge cavity through a pipeline. After the flow equalizing plate divides the gas, the divided gas first undergoes a first-stage cooling process through the hole array in the first-stage cooling chamber to reduce the kinetic energy of gas molecules. At the same time, the dust particles collide due to the reduced kinetic energy of the gas, separate from the gas, and fall onto the hole walls of the cooling through-holes in the hole array due to the gravity of the dust particles. Then the gas undergoes a second-stage cooling process in the second-stage cooling chamber to further reduce the kinetic energy of gas molecules, and the dust particles further collide and fall onto the hole walls or umbrella walls due to their own gravity. The dust particles in the gas are removed by the two-stage cooling process to improve the processing efficiency of the dust particles in the gas.

[0072] Application Scenario Two

[0073] In practical applications, the gas containing dust particles in the discharge cavity of an excimer laser enters the flow equalizing plate from the discharge cavity through a pipeline. After the flow equalizing plate divides the gas, the divided gas undergoes low-temperature dust removal treatment and electrostatic dust removal treatment respectively to improve the processing efficiency of the dust particles in the gas.

[0074] First, the gas undergoes low-temperature dust removal treatment as follows: First, it undergoes a first-stage cooling process through the hole array in the first-stage cooling chamber to reduce the kinetic energy of gas molecules. At the same time, the dust particles collide due to the reduced kinetic energy of the gas, separate from the gas, and fall onto the hole walls of the cooling through-holes due to the gravity of the dust particles. Second, the gas undergoes a second-stage cooling process in the second-stage cooling chamber to further reduce the kinetic energy of gas molecules, and the dust particles further collide and fall onto the hole walls or umbrella walls due to their own gravity.

[0075] Then, the gas undergoes electrostatic dust removal treatment. After the electrostatic dust removal device is powered on, a corona region is generated near the high-voltage electrode, where the dust particles are charged. Then, the charged dust particles migrate to the surface of the high-voltage electrode or the inner wall surface of the dust removal pipe under the action of the electric field generated between the high-voltage electrode and the inner wall of the dust removal pipe to remove the dust particles in the gas. In this embodiment, the dust removal efficiency of the dust particles in the gas is further improved through low-temperature dust removal and electrostatic dust removal.

[0076] Although this application is disclosed above with preferred embodiments, it is not intended to limit this application. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of this application. Therefore, the protection scope of this application should be determined by the scope defined in the claims of this application.

Claims

1. A dust removal device for the working gas of a laser resonator, characterized in that, Comprising: A cooling chamber that is at least connected to the laser resonator and includes an air inlet and an air outlet; The cooling chamber includes a plurality of air flow channels connecting the air inlet and the air outlet; when the gas to be cooled passes through the air flow channels, heat exchange occurs by contacting the walls of the air flow channels, so that the temperature of the gas to be cooled decreases; The cooling chamber includes a multi-stage cooling chamber with at least two stages, wherein the second-stage cooling chamber of the at least two-stage multi-stage cooling chamber includes an umbrella structure arranged coaxially, and a plurality of the umbrella structures are stacked in sequence along the axial direction of the second-stage cooling chamber, and there are gaps between adjacent umbrella structures.

2. The device according to claim 1, characterized in that, It further includes: a flow equalizing plate connected to the air inlet of the cooling chamber; The flow equalizing plate includes a plurality of flow equalizing holes each containing an air inlet and an air outlet; the gas to be cooled enters the air inlet of the cooling chamber through the flow equalizing holes.

3. The device according to claim 2, characterized in that, The flow equalizing plate includes at least one row of flow equalizing holes, and a plurality of equally spaced flow equalizing holes are arranged in the at least one row of flow equalizing holes, and at least one flow equalizing hole in the at least one row of flow equalizing holes is communicated with at least one air flow channel of the cooling chamber.

4. The device according to claim 2, characterized in that, The multi-stage cooling chamber with at least two stages includes a first-stage cooling chamber and a second-stage cooling chamber; The first-stage cooling chamber includes a uniformly distributed hole array, and each through hole in the hole array is a first-stage air flow channel; The umbrella structure in the second-stage cooling chamber includes at least one ring, and the gap between adjacent rings is a second-stage air flow channel; The gas to be cooled undergoes a first cooling process through the first-stage air flow channel and then undergoes a second cooling process through the second-stage air flow channel.

5. The device according to claim 4, characterized in that, The cooling chamber is arranged in a symmetric structure, and one side of the symmetric two sides of the cooling chamber respectively includes a flow equalizing plate, the first-stage cooling chamber and the second-stage cooling chamber that are interconnected; The gas to be cooled enters the first-stage cooling chamber through the flow equalizing plates on both symmetric sides respectively, and then enters the second-stage cooling chamber.

6. The device according to claim 4, characterized in that, The second-stage air flow channel is longer than the first-stage air flow channel.

7. The device according to claim 1, characterized in that, It further includes: An electrostatic dust removal chamber communicated with the cooling chamber, and the electrostatic dust removal chamber is arranged in series with the cooling chamber; The electrostatic dust removal chamber includes a dust removal pipe and a high-voltage electrode arranged at the central position of the dust removal pipe, and an electric field intersecting the air flow direction is formed between the high-voltage electrode and the pipe wall of the dust removal pipe when powered on.

8. An excimer laser, characterized in that, Comprising: Using the dust removal device for the working gas of the laser resonator as described in claim 1.

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