Coating cleaning method and gas diffusion device

Abstract

The application discloses a coating cleaning method and a gas diffusion device. The coating cleaning method comprises the following steps: providing a component to be treated, wherein the component to be treated comprises a component body and a corrosion-resistant coating containing yttrium or zirconium which is covered on the surface of the component body; the surface of the corrosion-resistant coating comprises a pollution layer, and the pollution layer contains halogen elements; introducing acid gas or acid vapor to the pollution layer to react with the pollution layer; and ultrasonic cleaning, megasonic cleaning or high-pressure flushing the pollution layer to make the pollution layer fall off from the surface of the corrosion-resistant coating. The amount and time of the introduced gas are controlled, so that the pollution layer is just removed without excessively affecting the corrosion-resistant coating.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of semiconductor, in particular to a coating cleaning method and a gas diffusion device. BACKGROUND

[0002] Components of a plasma processing device are exposed to a plasma environment and are susceptible to damage by plasma etching. An erosion-resistant coating is typically applied to the surface of the components to protect the components. Over time, the surface of the erosion-resistant coating can still react with the plasma and form a contamination layer, which can cause the erosion-resistant coating to fail. In order to continue using the erosion-resistant coating, the contamination layer on the surface of the erosion-resistant coating needs to be removed.

[0003] The prior art uses an acid solution cleaning method to remove the contamination layer. The solution has fluidity, and the corrosion of the acid solution is high, and the degree of corrosion of the contamination layer is uncontrollable, and other areas of the components that do not need to be cleaned can also be damaged. Even if the method of dipping the acid solution for wiping and cleaning is used, due to the difficulty in controlling the wiping force and the amount of acid solution, the uniformity of the removal of the contamination layer cannot be guaranteed. SUMMARY

[0004] The purpose of the present application is to solve the problem of uneven and uncontrollable removal of the contamination layer.

[0005] In order to achieve the above purpose, the present application provides a coating cleaning method, comprising:

[0006] providing a to-be-processed component, the to-be-processed component comprising a component body and an erosion-resistant coating containing yttrium or zirconium covering the surface of the component body;

[0007] the surface of the erosion-resistant coating comprises a contamination layer, and the contamination layer contains halogen elements;

[0008] supplying an acid gas or an acid vapor to the contamination layer to react with the contamination layer;

[0009] ultrasonic cleaning, megasonic cleaning or high-pressure flushing the contamination layer to make the contamination layer fall off from the surface of the erosion-resistant coating.

[0010] Optionally, the erosion-resistant coating contains yttrium oxide.

[0011] Optionally, the contamination layer contains yttrium oxyfluoride and / or yttrium fluoride.

[0012] Optionally, the acid gas is hydrogen chloride gas; and the acid vapor contains hydrogen chloride and / or nitric acid.

[0013] Optionally, the contamination layer is ultrasonically cleaned, megasonically cleaned or high-pressure flushed using an aqueous solution or pure water.

[0014] Optionally, after the ultrasonic cleaning, megasonic cleaning or high pressure flushing of the contaminated layer, the component to be treated is dried.

[0015] Optionally, when the acid gas or acid vapor is introduced into the contaminated layer to react with the contaminated layer, the acid gas or acid vapor is continuously flowed through the contaminated layer.

[0016] Optionally, the acid gas or acid vapor is introduced into the contaminated layer under vacuum.

[0017] Optionally, the step of introducing the acid gas or acid vapor into the contaminated layer and the step of ultrasonic cleaning, megasonic cleaning or high pressure flushing of the contaminated layer are repeated until the contaminated layer is detached from the surface of the corrosion resistant coating.

[0018] Optionally, before the acid gas or acid vapor is introduced into the contaminated layer, the portion of the component that does not need to be cleaned is covered with a shielding member.

[0019] Optionally, the component to be treated is at least one of a cover plate, a ceramic window, a chamber liner, a nozzle, a gas distribution plate, a shower head, a ring assembly of an electrostatic chuck, and a ceramic gasket.

[0020] The present application also provides a gas diffusion device for the coating cleaning method described above, comprising a reaction chamber, a carrier, an inlet pipe and a vacuum pump; the carrier is disposed in the reaction chamber and used to carry the component to be treated; the vacuum pump is in communication with the reaction chamber; the inlet pipe is in communication with the reaction chamber and used to introduce acid gas or acid vapor into the reaction chamber; the acid gas or acid vapor flows through the surface of the contaminated layer in the reaction chamber.

[0021] Optionally, when the acid vapor is introduced into the reaction chamber, the gas diffusion device further comprises a vapor generating device.

[0022] The vapor generating device comprises a container, a gas inlet pipe and a gas outlet pipe; the container carries an acid liquid; the gas outlet pipe is in communication with the inlet pipe.

[0023] A carrier gas is introduced into the gas inlet pipe, so that the acid liquid is introduced into the reaction chamber in the form of acid vapor through the gas outlet pipe.

[0024] Optionally, the carrier gas is argon and / or nitrogen.

[0025] Optionally, a flow controller is installed on the gas inlet pipe.

[0026] The present application has the following advantages:

[0027] (1) The coating cleaning method of the present application, the acid gas or acid vapor is supplied to the pollution layer of the component, reacts with the oxide in the pollution layer, and by controlling the supply time, concentration, etc. of the gas or vapor, the removal thickness of the pollution layer can be accurately controlled.

[0028] (2) The gas or vapor has good diffusivity and uniformity, can uniformly diffuse on the surface of the pollution layer, and penetrate into the microcracks of the pollution layer, enter the inside of the microcracks, and make the reaction degree of the pollution layer more sufficient.

[0029] (3) For the area of the component that is easy to react with acid but does not need to be removed, the area can be protected by covering the shielding piece. The shielding piece is not easy to fall off from the component in the acid gas or acid vapor environment, and can effectively protect the component. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the component before use.

[0031] Figure 2 It is a schematic diagram of the structure of the component after being used for a period of time.

[0032] Figure 3 It is a flow chart of the coating cleaning method provided by the present application.

[0033] Figure 4 It is a schematic diagram of the structure of the component cleaned by using the coating cleaning method provided by the present application.

[0034] Figure 5 It is a schematic diagram of the structure of the gas diffusion device provided by the present application.

[0035] Figure 6 It is a schematic diagram of the structure of the vapor generation device provided by the present application.

[0036] In the figure, 1 is the component body, 2 is the corrosion-resistant coating layer, 3 is the pollution layer, 4 is the reaction cavity, 5 is the carrier, 6 is the inlet pipeline, 7 is the vacuum pump, 8 is the container, 9 is the gas inlet pipe, and 10 is the gas outlet pipe. DETAILED DESCRIPTION

[0037] The technical solutions of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0038] In the description of the present application, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0039] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection; it can be directly connected, or indirectly connected through intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0040] Because the plasma contains a large number of active particles such as electrons, ions, excited state atoms, molecules and free radicals, the components such as metal, quartz and anodized aluminum exposed to the plasma environment are easily eroded by the plasma. As shown in Figure 1 In order to protect these components, a corrosion-resistant coating 2 containing yttrium or zirconium elements is usually coated on the surface of the component body 1. In some embodiments, the corrosion-resistant coating 2 contains yttrium oxide.

[0041] As shown in Figure 2 After being used for a period of time, the surface of the corrosion-resistant coating 2 will still react with the plasma under the bombardment of the plasma to form a pollution layer 3 containing halogen elements, causing the corrosion-resistant coating 2 to fail. Therefore, it is necessary to periodically remove the pollution layer 3 to expose the corrosion-resistant coating 2 again, so that the component can maintain normal function.

[0042] The prior art uses an acid solution to clean the pollution layer 3. Because the pollution layer 3 formed by the halogen elements and the corrosion-resistant coating 2 has a stable chemical structure, the acid solution actually reacts with the oxides in the pollution layer 3 to generate products that are dissolved in water and then separated from the pollution layer 3, so that the pollution layer 3 forms a loose structure containing holes. Then, vibration is applied to the pollution layer 3 to make the loose pollution layer 3 fall off the surface of the corrosion-resistant coating 2. However, the solution has fluidity, and the corrosion of the acid solution is too high, so the degree of corrosion of the pollution layer 3 is uncontrollable, and at the same time, the corrosion-resistant coating 2 also contains a large amount of oxides, which will react with the acid solution to reduce the service life of the corrosion-resistant coating 2.

[0043] It should be noted that the surface of the corrosion-resistant coating 2 is directly bombarded by the plasma, yttrium fluoride and yttrium oxyfluoride are not only generated and attached to the surface of the corrosion-resistant coating 2, but also react the yttrium oxide inside the corrosion-resistant coating 2 into yttrium fluoride or yttrium oxyfluoride, and the yttrium fluoride or yttrium oxyfluoride is not uniformly formed on the surface of the corrosion-resistant coating 2, and the depth of the yttrium fluoride or yttrium oxyfluoride is also inconsistent, so on the corrosion-resistant coating 2, the part where the yttrium fluoride or yttrium oxyfluoride is generated belongs to the pollution layer 3 defined in the present application, that is, the pollution layer 3 is not a layer structure with consistent thickness, and the pollution layer 3 also contains unreacted yttrium oxide.

[0044] Furthermore, the applicant has further found that the pollution layer 3 is not a completely dense structure, and micro-cracks are formed on the pollution layer 3. The liquid has surface tension, and the acid solution is difficult to penetrate into these micro-cracks, and can only react with the outer layer of the pollution layer 3, and cannot penetrate, so that some of the pollution layer 3 inside the corrosion-resistant coating 2 cannot react with the acid.

[0045] As shown in Figure 3 , the present application provides a coating cleaning method, comprising:

[0046] Step S1: providing a to-be-processed component.

[0047] The structure of the to-be-processed component is as shown in Figure 2 , which comprises a component body 1, a corrosion-resistant coating 2 containing yttrium or zirconium covering the surface of the component body 1, and a pollution layer 3 generated after the corrosion-resistant coating 2 reacts. Figure 2 It is only a structural schematic diagram, and there may be cracks on the corrosion-resistant coating 2 and the pollution layer 3.

[0048] In some embodiments, the corrosion-resistant coating 2 contains yttrium oxide. The surface of the corrosion-resistant coating 2 includes a pollution layer 3 containing halogen elements. In some embodiments, under the bombardment of the fluorine-containing plasma, the yttrium oxide on the surface of the corrosion-resistant coating 2 reacts with the fluorine-containing plasma to generate a pollution layer 3 containing yttrium fluoride and / or yttrium oxyfluoride.

[0049] In some embodiments, the to-be-processed component is at least one of a cover plate, a ceramic window, a chamber lining, a nozzle, a gas distribution plate, a shower head, a ring assembly of an electrostatic chuck, and a ceramic gasket.

[0050] Step S2: supplying an acid gas or an acid vapor to the pollution layer 3 to react with the pollution layer 3.

[0051] In an ideal state, the contamination layer 3 is completely removed without over-cleaning, which damages the non-corrosion coating 2. If the contamination layer 3 is not completely removed, as described above, the acid-treated contamination layer 3 contains porous structures, which, after the part is continuously used, are removed from the non-corrosion coating 2 under the bombardment of plasma and become the source of particles in the plasma device, causing contamination in the device. If over-cleaning occurs, the acid reacts with the non-corrosion coating 2 after the contamination layer 3 is removed, which thins the non-corrosion coating 2 and reduces the service life of the part.

[0052] The present application introduces an acid gas or an acid vapor to the contamination layer 3 to react with the contamination layer 3. The diffusion and uniformity of the gas are better than those of the liquid. The acid gas or the acid vapor supplied to the contamination layer 3 can control the removal amount of the contamination layer 3 by controlling the time and concentration of the gas supply. For the micro-cracks on the contamination layer 3, the acid gas or the acid vapor can penetrate into the interior of the micro-cracks, making the reaction more sufficient.

[0053] In some embodiments, the acid gas is hydrogen chloride gas; and the acid vapor contains hydrogen chloride and / or nitric acid.

[0054] In some embodiments, the acid gas or the acid vapor is continuously supplied to the contamination layer 3 to react with the contamination layer 3.

[0055] In some embodiments, the acid gas or the acid vapor is supplied to the contamination layer 3 in a vacuum environment.

[0056] In addition to the area coated with the non-corrosion coating 2 containing oxides, some parts to be treated also contain oxides or substances that are easy to react with acid, such as the area treated by anodic oxidation. In some embodiments, before the acid gas or the acid vapor is introduced to the contamination layer 3, a shielding member is used to cover the part that does not need to be cleaned to protect the part from reacting with the acid. The shielding member can be a tape, a cover plate, etc. Since the tape will lose adhesion in the acid solution and peel off, the cover plate is not stable enough in the acid solution, and the performance and use effect of the shielding member are almost not affected by the gas. The use of the shielding member in the cleaning method provided by the present application can more effectively protect the part that does not need to be cleaned.

[0057] Step S3: ultrasonic cleaning, megasonic cleaning, or high-pressure flushing of the contamination layer 3 to make the contamination layer 3 fall off from the surface of the non-corrosion coating 2.

[0058] The acid gas or acid vapor reacts with the oxide in the contaminated layer 3 to form a salt which is soluble in water. After the salt is dissolved in water, the contaminated layer 3 forms a loose structure with holes. The contaminated layer 3 can be removed from the surface of the corrosion-resistant coating 2 under the action of external forces such as vibration. The cleaned part is shown in Figure 4

[0059] In some embodiments, the contaminated layer 3 is cleaned by ultrasonic cleaning, megasonic cleaning or high-pressure flushing using an aqueous solution or pure water. The solute of the aqueous solution does not react with the corrosion-resistant coating 2. For example, when the acid source in the acid gas or acid vapor is hydrogen chloride, the solute can be selected as sodium chloride; when the acid vapor is nitric acid, the solute can be selected as sodium nitrate.

[0060] In some embodiments, after the contaminated layer 3 is cleaned by ultrasonic cleaning, megasonic cleaning or high-pressure flushing, the part to be treated is dried.

[0061] In some embodiments, steps S2 and S3 are repeated until the contaminated layer 3 is removed from the surface of the corrosion-resistant coating 2.

[0062] As shown in Figure 5 The present application also provides a gas diffusion device for the coating cleaning method described above, which comprises a reaction chamber 4, a carrier 5, an inlet pipe 6 and a vacuum pump 7. The carrier 5 is placed in the reaction chamber 4 and used to carry the part to be treated. The vacuum pump 7 is in communication with the reaction chamber 4. The inlet pipe 6 is in communication with the reaction chamber 4 and used to introduce acid gas or acid vapor into the reaction chamber 4. The acid gas or acid vapor flows through the surface of the contaminated layer 3 in the reaction chamber 4.

[0063] In some embodiments, when the acid vapor is introduced into the reaction chamber 4, the gas diffusion device further comprises a vapor generation device as shown in Figure 6 The vapor generation device comprises a container 8, an inlet pipe 9 and an outlet pipe 10. The container 8 is filled with an acid liquid. The outlet pipe 10 is in communication with the inlet pipe 6. A carrier gas is introduced into the inlet pipe 9 so that the acid liquid is introduced into the reaction chamber 4 in the form of acid vapor through the outlet pipe 10. Optionally, the carrier gas is argon and / or nitrogen. Optionally, a flow controller is installed on the inlet pipe 9.

[0064] Embodiment

[0065] The present embodiment provides a coating cleaning method, which comprises:

[0066] Step S1: providing a part to be treated.

[0067] ​The component to be treated includes a component body 1 and a corrosion resistant coating 2 covering the surface of the component body 1. The corrosion resistant coating 2 is a yttrium oxide coating. After the component to be treated is operated in a fluorine-containing plasma environment for a period of time, the fluorine-containing plasma reacts with the yttrium oxide in the corrosion resistant coating 2 to form a contaminated layer 3 on the surface of the corrosion resistant coating 2, which contains yttrium fluoride and yttrium oxyfluoride.

[0068] When the yttrium oxide in the corrosion resistant coating 2 reacts to form yttrium fluoride or yttrium oxyfluoride, micro-cracks are formed in the contaminated layer 3 due to the volume change of the crystal grains during the reaction. Further bombardment of the contaminated layer 3 with the micro-cracks by the plasma easily forms particulate matter, which is a mixture of yttrium oxide, yttrium fluoride and yttrium oxyfluoride, causing particulate contamination in the reaction device. Since the liquid has surface tension, the acid solution is difficult to penetrate into the micro-cracks to participate in the reaction, and the penetration is not uniform, making it difficult to completely remove the oxide crystal grains in the contaminated layer 3.

[0069] Step S2: introducing hydrochloric acid vapor into the contaminated layer 3 to react with the contaminated layer 3.

[0070] The contaminated layer 3 contains yttrium oxide, yttrium fluoride and yttrium oxyfluoride. The chemical structures of yttrium fluoride and yttrium oxyfluoride are quite stable and do not react with hydrochloric acid. Yttrium oxide can react with hydrochloric acid to form yttrium chloride. This embodiment uses a gas diffusion device as shown in Figure 5 The component is placed on the stage 5 in the reaction chamber 4, and the outlet of the inlet pipe 6 in the reaction chamber 4 is opposite to the component to be treated. The vacuum pump 7 is turned on, and hydrochloric acid vapor is introduced into the reaction chamber 4 through the inlet pipe 6, so that the hydrochloric acid vapor continuously flows over the surface of the contaminated layer 3 in the reaction chamber 4. This embodiment uses a vapor generation device as shown in Figure 6 The concentration, amount and time of introduction of the hydrochloric acid vapor are controlled to quantitatively remove the contaminated layer 3. Based on the good uniformity and flowability of the gas, the hydrochloric acid vapor can penetrate into the micro-cracks of the contaminated layer 3, ensuring complete removal of the contaminated layer 3 and ensuring sufficient reaction of the oxide crystal grains in the contaminated layer 3 with the vapor.

[0071] In this embodiment, a cover plate is covered on the anodization area and the corrosion resistant coating 2 without the formation of the contaminated layer 3 as a shielding member to shield these parts from reacting with the hydrochloric acid vapor.

[0072] Step S3: ultrasonic cleaning of the contaminated layer 3 to make the contaminated layer 3 fall off from the surface of the corrosion resistant coating 2.

[0073] After a period of time, the vacuum pump 7 and the carrier gas are turned off and the component is removed. The component is placed in ultrapure water and cleaned using ultrasonic waves. After the yttrium chloride is dissolved in the ultrapure water, the contamination layer 3 becomes a loose, porous structure. After ultrasonic oscillation, the loose contamination layer 3 falls off the surface of the corrosion-resistant coating 2. After 30 minutes of cleaning, the component is removed and dried in a dry box at 120°C and filled with high-purity N2for 6 hours. After drying is complete, the component is removed and packaged.

[0074] In summary, the present application provides a coating cleaning method. After a component is bombarded by plasma to form a contamination layer on the surface of the component, an acidic gas or an acidic vapor is supplied to the surface of the component. The supplied acidic gas or acidic vapor reacts with the contamination layer. The concentration, amount, and time of the supplied acidic gas or acidic vapor are controlled to quantitatively remove the contamination layer. Because the gas has good uniformity and flowability, the gas can penetrate into the microcracks of the contamination layer, ensure sufficient reaction, and ensure complete removal of the contamination layer. Finally, the contamination layer is removed from the surface of the corrosion-resistant coating by ultrasonic cleaning, megasonic cleaning, or high-pressure washing.

[0075] Although the present application has been described in detail by the above preferred embodiments, it should be understood that the above description should not be considered as limiting the present application. After reading the above description, various modifications and alternatives to the present application will be apparent to those skilled in the art. Therefore, the scope of the present application should be defined by the appended claims.

Claims

1. A coating cleaning method characterized by, The method comprises: providing a component to be treated, which comprises a component body and a corrosion-resistant coating layer containing yttrium or zirconium on the surface of the component body; the surface of the corrosion-resistant coating layer comprises a contaminated layer containing halogen elements; supplying an acid gas or an acid vapor to the contaminated layer to react with the contaminated layer; ultrasonic cleaning, megasonic cleaning or high-pressure flushing of the contaminated layer to make the contaminated layer fall off from the surface of the corrosion-resistant coating layer.

2. The coating cleaning method according to claim 1, wherein when the corrosion-resistant coating layer contains yttrium, the corrosion-resistant coating layer contains yttrium oxide.

3. The coating cleaning method according to claim 2, wherein the contaminated layer contains yttrium oxyfluoride and / or yttrium fluoride.

4. The coating cleaning method of claim 1, wherein, the acid gas is hydrogen chloride gas; the acid vapor contains hydrogen chloride and / or nitric acid.

5. The coating cleaning method of claim 1, wherein, the contaminated layer is ultrasonically cleaned, megasonically cleaned or high-pressure flushed using an aqueous solution or pure water.

6. The coating cleaning method of claim 1, wherein, after the contaminated layer is ultrasonically cleaned, megasonically cleaned or high-pressure flushed, the component to be treated is dried.

7. The coating cleaning method of claim 1, wherein when the acid gas or acid vapor is introduced to the contaminated layer to react with the contaminated layer, the acid gas or acid vapor is continuously supplied to the contaminated layer.

8. The coating cleaning method of claim 1, wherein the acid gas or acid vapor is introduced to the contaminated layer in a vacuum environment.

9. The coating cleaning method of claim 1, wherein, the step of introducing the acid gas or acid vapor to the contaminated layer and the step of ultrasonically cleaning, megasonically cleaning or high-pressure flushing the contaminated layer are repeated until the contaminated layer falls off from the surface of the corrosion-resistant coating layer.

10. The coating cleaning method of claim 1, wherein before the acid gas or acid vapor is introduced to the contaminated layer, the non-cleaned part of the component is covered with a shielding member.

11. The coating cleaning method of claim 1, wherein the component to be treated is a cover plate, a ceramic window, a chamber lining, a nozzle, a gas distribution plate, a shower head, a ring assembly of an electrostatic chuck or a ceramic gasket.

12. A gas diffusion device characterized by, a coating cleaning apparatus for the coating cleaning method as claimed in any one of claims 1-11, which comprises a reaction chamber, a carrier, an inlet pipe and a vacuum pump; the carrier is arranged in the reaction chamber and used to carry the component to be treated; the vacuum pump is in communication with the reaction chamber; the inlet pipe is in communication with the reaction chamber and used to introduce the acid gas or acid vapor into the reaction chamber; the acid gas or acid vapor flows through the surface of the contaminated layer in the reaction chamber.

13. The gas diffusion device of claim 12, wherein when the acid vapor is introduced into the reaction chamber, the apparatus further comprises a vapor generating device; the vapor generating device comprises a container, a gas inlet pipe and a gas outlet pipe; the container carries an acid liquid; the gas outlet pipe is in communication with the inlet pipe; carrier gas is introduced into the gas inlet pipe so that the acid liquid is introduced into the reaction chamber in the form of acid vapor through the gas outlet pipe.

14. The gas diffusion device of claim 13, wherein the carrier gas is argon and / or nitrogen.

15. The gas diffusion device of claim 13, wherein a flow controller is installed on the gas inlet pipe.

Images