AU2019101816A4

AU2019101816A4 - Method for preparing protective coating for plasma etching chamber of IC equipment

Info

Publication number: AU2019101816A4
Application number: AU2019101816A
Authority: AU
Inventors: Xinyu CUI; Tao HOU; Yanfang Shen; Tianying Xiong; Guangwen ZHENG
Original assignee: Shenyang Fortune Precision Equipment Co Ltd
Current assignee: Shenyang Fortune Precision Equipment Co Ltd
Priority date: 2019-02-22
Filing date: 2019-07-22
Publication date: 2021-09-09
Anticipated expiration: 2027-07-22
Also published as: CN109825827A; ZA202105559B; WO2020168679A1

Abstract

A preparation method of a protective coating for an IC equipment plasma etching chamber is disclosed, which includes: depositing a mixed powder of Al and Y203-ZrO2 at a high speed by a cold spraying deposition technology, wherein during the cold spraying, compressed air serves as a working gas, a spraying distance is 10 to 60 mm, a spraying temperature is 200 to 600°C, a gas pressure is 1.5 to 3 MPa and a particle size of the powder is 1 to 50 m; and forming a uniformly distributed cermet protective coating on a surface of the plasma etching chamber. The coating can reduce or prevent corrosion of corrosive gases to the etching chamber and contamination of plasma to a chip, and prolong the service life of the plasma etching chamber during chip production. First, an Al powder and a Y203-ZrO2 powder are uniformly mixed according to proportion, and dried; then the mixed powder is sprayed onto a surface of a matrix by a cold spraying deposition technology; and finally a cermet composite coating is obtained by controlling process parameters. The method has high deposition efficiency, the thickness of the coating can be adjusted according to practical applications, and the method can be used to prepare a thick protective coating for an IC equipment plasma etching chamber.

Description

PREPARATION METHOD OF PROTECTIVE COATING FOR IC EQUIPMENT PLASMA ETCHING CHAMBER

Field of the Invention The present disclosure relates to the technical field of preparation of cermet coatings, and in particular, to a preparation method of a protective coating for an IC equipment plasma etching chamber. Background of the Invention In most previous studies, a thermal spraying device was used to prepare an YSZ coating, which needed to be heated to above 2000°C under harsh conditions and at a high cost. There are transverse cracks on the outermost layer of the coating, its compactness is poor, and its quality needs to be improved. When a cold spraying technology is used for preparing a ceramic coating, the nature of ceramic powder used is critical. Common nanopowders are not suitable for preparing coatings by cold spraying because a high-pressure and high-speed airflow of cold spraying will form bow shocks on a surface of a matrix to hinder the deposition of the nanopowder. However, when the size of spraying particles is too large, erosion will occur on the matrix, and therefore it is difficult to form a coating. Therefore, to prepare YSZ ceramic coatings by cold spraying, it is very important to prepare YSZ powder suitable for cold spraying. The current international trend is to study yttria-stabilized zirconia ceramic coatings to improve the overall performance of the coatings. Seok, et al. (Seok H W, Kim Y C, Chol E Y, et al. Multi-component thermal spray coating material and production method and coating method thereof: US, 13/915976 [P]. 2013-06-12.) prepared several etching-resistant coatings, such as an A1 2 0 3 coating, a Y 2 0 3 coating, Y203-ZrO2 coatings with different yttria content, and a Y203-ZrO2-Al203 coating, by an atmospheric plasma spraying method, tested their etching rates, and made a conclusion that: the etching rate of the Y203-ZrO coating is substantially lower than that of the yttria coating, and when Y 2 0 3 : ZrO2 is 70: 30, the etching rate of the coating is the lowest, about 5 nm/min, that is to say, the best plasma etching resistance is obtained. Summary of the Invention In view of the above-mentioned deficiencies existing in the prior art, the present disclosure is directed to provide a preparation method of a protective coating for an IC equipment plasma etching chamber, which solves the problem that the current protective coating for the IC equipment plasma etching chamber is vulnerable to failure in a high-power etching process, opens up a novel effective way for preparing a protective coating for an IC equipment plasma etching chamber, and is expected to realize practical applications as early as possible. To achieve the above object, the present disclosure adopts the following technical solutions: a preparation method of a protective coating for an IC equipment plasma etching chamber includes: preparing a protective coating for a surface of a plasma etching chamber body by using a mixed powder of Al and Y203-ZrO2, directly spraying the mixed powder of Al and Y203-ZrO2 on the surface of the plasma etching chamber body by using a high-speed airflow, wherein spraying parameters are as follows: compressed air serves as a working gas, a gas temperature is 200 to 600°C, a gas pressure is 1.5 to 3.0 MPa, and a spraying distance is 10 to 60 mm; and depositing the mixed powder on an inner surface of a plasma etching chamber to form a uniformly distributed protective coating, wherein a weight ratio of an Al powder to a Y203-ZrO2 powder is (0.1-1): 1, and in the Y203-ZrO2 powder, a weight ratio of a Y 2 0 3 powder to a ZrO2 powder is (3 5): 1. (1) Preparation of a micron-sized mixed powder: mixing an Al powder and a Y203-ZrO2 powder in a weight ratio of (0.1-1): 1, wherein in the Y203-ZrO2 powder, a weight ratio of a Y 2 0 3 powder to a ZrO2 powder is (3-5): 1, and drying the mixed powder to obtain a micron-sized mixed powder with a particle size of 1 to 50 m; (2) Cold spraying deposition of a protective coating for a plasma etching chamber: depositing the micron-sized mixed powder obtained at step (1) on an inner surface of a material of an etching chamber after being preheated by compressed air to obtain a protective coating for the plasma etching chamber, wherein during the cold spraying deposition, the compressed air serves as a working gas, a working gas temperature is 200 to 600°C, a working gas pressure is 1.5 to 3.0 MPa, and a spraying distance is 10 to 60 mm. A spraying apparatus for a protective coating for a plasma etching chamber includes an air inlet pipe 1, a heater 2, a powder feeder 5, an electromagnetic valve 6, a supersonic nozzle 4, and a control cabinet 1, wherein one end of the air inlet pipe is connected to an air compressor, the other end of the air inlet pipe is connected to the powder feeder, the heater, and the supersonic nozzle, and a part, placed in the heater, of the air inlet pipe has a spiral structure. In the process of preparing a protective coating for a plasma etching chamber, a working gas output by the air compressor is divided into two parts, one part enters the heater, and then enters a mixing cavity of the supersonic nozzle after being preheated; the other part enters the powder feeder, and as a carrier gas, introduces a powder into the supersonic nozzle to be mixed with the first part of gas which is preheated; after instantaneously preheating the powder, the gas passes through a convergent-divergent region of the supersonic nozzle and expands and accelerates to form a supersonic gas solid two-phase flow which impacts on an inner surface of a material of the etching chamber at a high speed to make the powder deform severely to realize deposition, and a composite protective coating is formed on the inner surface of the material of the etching chamber. A porosity of the protective coating is less than 2%, an interface bonding strength between a ceramic coating and a matrix material is 20 to 50 MPa, and a thickness of the coating is 10 to 400 [m. The advantages and beneficial effects of the present disclosure are that: by the cold spraying deposition technology, the present disclosure can prepare a protective coating with a thicknesses of 10 to 400 um for an IC equipment plasma etching chamber by only taking relatively low-cost compressed air as a carrier gas. The method has high deposition efficiency, the thickness of the coating can be adjusted according to practical applications, and the method can be used to prepare a thick protective coating for an IC equipment plasma etching chamber. Brief Description of the Drawings Fig. 1 is a schematic diagram of a spraying apparatus according to the present disclosure. Detailed Description of the Embodiments The present disclosure will be described in detail with reference to Fig. 1 and embodiments. A preparation method of a protective coating for an IC equipment plasma etching chamber includes the following steps: (1) Preparation of a micron-sized mixed powder: an Al powder and a Y203-ZrO2 powder are mixed in a weight ratio of (0.1-1): 1, wherein in the Y203-ZrO2 powder, a weight ratio of a Y 2 0 3 powder to a ZrO2 powder is (3-5): 1, and the mixed powder is dried to obtain a micron-sized mixed powder with a particle size of 1 to 50 m; (2) Cold spraying deposition of a protective coating for a plasma etching chamber: the micron-sized mixed powder obtained at step (1) is deposited on an inner surface of a material of the etching chamber with high throughout after being preheated by heated compressed air to obtain a protective coating for the plasma etching chamber, wherein during the cold spraying deposition, the compressed air serves as a working gas, a working gas temperature is 200 to 600°C, a working gas pressure is 1.5 to 3.0 MPa, and a spraying distance is 10 to 60 mm. In the above step (1), a weight ratio of the pure Al powder to the Y203-ZrO2 powder is (0.1-1): 1. In the above step (1), a weight ratio of the Y 2 0 3 powder to the ZrO2 powder is (3 5): 1. In the above step (1), the micron-sized Al powder and the Y203-ZrO2 powder are dried to obtain a micron-sized mixed powder with a particle size of 1 to 50 m. In the above step (2), the working gas is compressed air. In the above step (2), the deposition process parameters are as follows: a working gas temperature is 200 to 600°C, a working gas pressure is 1.5 to 3.0 MPa, and a spraying distance is 10 to 60 mm. A protective coating for an IC equipment plasma etching chamber is prepared by the above method, and a porosity of the protective coating is less than 2%, an interface bonding strength between a ceramic coating and a matrix material is 20 to 50 MPa, and a thickness of the coating is 10 to 400 [m. According to the present disclosure, the Al powder and the Y203-ZrO2 powder are mixed in the weight ratio of (0.1-1): 1, wherein in the Y203-ZrO2 powder, the weight ratio of the Y 2 0 3 powder to the ZrO2 powder is (3-5): 1, and the mixed powder is dried to obtain the micron-sized mixed powder with the particle size of 1 to 50 m. The micron-sized mixed powder obtained at step (1) is deposited on the inner surface of the material of the etching chamber after being preheated by the heated compressed air to obtain the protective coating for the plasma etching chamber, wherein during the cold spraying deposition, the compressed air serves as the working gas, the working gas temperature is 200 to 600°C, the working gas pressure is 1.5 to 3.0 MPa, and the spraying distance is 10 to 60 mm. Embodiment 1

In the present embodiment, a protective coating for an IC equipment plasma etching chamber was prepared on a 6061 alloy matrix. The specific steps of the preparation method were as follows: (1) 20 g of pure Al powder, 160 gof Y 2 0 3 powder and 40 g of ZrO2 powder were weighed, mixed and dried for later use; and (2) an Al+(Y203-ZrO2) composite coating with a thickness of about 180 m was prepared on the 6061 alloy matrix by taking the micron-sized Al+(Y203-ZrO2) mixed powder prepared at step (1) as a spraying powder and adopting a cold spraying deposition technology. The cold spraying process conditions for preparing the coating were as follows: compressed air served as a working gas, a gas temperature was 400°C, a gas pressure was 2.0 MPa, and a spraying distance was 20 mm. The Al+(Y203-ZrO2) composite coating prepared in the present embodiment had a porosity of 2.0%, and an interface bonding strength between the coating and the matrix material was 45 MPa. Embodiment 2 In the present embodiment, a protective coating for an IC equipment plasma etching chamber was prepared on an Al matrix. The specific steps of the preparation method were as follows: (1) 30 g of pure Al powder, 240 gof Y 2 0 3 powder and 60 g of ZrO2 powder were weighed, mixed and dried for later use; and (2) an Al+(Y203-ZrO2) composite coating with a thickness of about 150 m was prepared on the Al matrix by taking the micron-sized Al+(Y203-ZrO2) mixed powder prepared at step (1) as a spraying powder and adopting a cold spraying deposition technology. The cold spraying process conditions for preparing the coating were as follows: compressed air served as a working gas, a gas temperature was 500°C, a gas pressure was 2.2 MPa, and a spraying distance was 25mm. The Al+(Y203-ZrO2) composite coating prepared in the present embodiment had a porosity of 1.8%, and an interface bonding strength between the coating and the matrix material was 43 MPa. Embodiment 3 In the present embodiment, a protective coating for an IC equipment plasma etching chamber was prepared on a 6061 alloy matrix. The specific steps of the preparation method were as follows: (1) 15 g of pure Al powder, 90 gof Y 2 0 3 powder and 30 g of ZrO2 powder were weighed, mixed and dried for later use; and (2) an Al+(Y203-ZrO2) composite coating with a thickness of about 220 m was prepared on the 6061 alloy matrix by taking the micron-sized Al+(Y203-ZrO2) mixed powder prepared at step (1) as a spraying powder and adopting a cold spraying deposition technology. The cold spraying process conditions for preparing the coating were as follows: compressed air served as a working gas, a gas temperature was 600°C, a gas pressure was 2.3 MPa, and a spraying distance was 20mm. The Al+(Y203-ZrO2) composite coating prepared in the present embodiment had a porosity of 1.9%, and an interface bonding strength between the coating and the matrix material was 40 MPa. Results of the above embodiments show that according to the protective coating for the IC equipment plasma etching chamber prepared in the present disclosure, a micron-sized agglomerated YSZ powder with a nanocrystalline structure is first prepared by using a surfactant and adopting a hydrothermal method, and then an YSZ coating is prepared by a cold spraying technology. The coating is well bound to the matrix, and has a porosity of less than 2%, an interface bonding strength of 20 to 50 MPa, and a thickness of 10 to 400 [m. The above detailed implementations and specific operation process are described with reference to the technical solutions of the present disclosure, but it should be understood that the scope of protection of the present disclosure is not limited to the embodiments described above.

Claims

Claims 1. A preparation method of a protective coating for an IC equipment plasma etching chamber, characterized by comprising: preparing a protective coating for a surface of a plasma etching chamber body by using a mixed powder of Al and Y 2 0 3 ZrO2, directly spraying the mixed powder of Al and Y203-ZrO2 on the surface of the plasma etching chamber body by using a high-speed airflow, wherein spraying parameters are as follows: compressed air serves as a working gas, a gas temperature is 200 to 600°C, a gas pressure is 1.5 to 3.0 MPa, and a spraying distance is 10 to 60 mm; and depositing the mixed powder on an inner surface of the plasma etching chamber to form a uniformly distributed protective coating, wherein a weight ratio of an Al powder to a Y203-ZrO2 powder is (0.1-1): 1, and in the Y203-ZrO2 powder, a weight ratio of a Y 2 0 3 powder to a ZrO2 powder is (3-5): 1.
2. The preparation method of the protective coating for the IC equipment plasma etching chamber according to claim 1, characterized by comprising: (1) Preparation of a micron-sized mixed powder: mixing an Al powder and a Y203-ZrO2 powder in a weight ratio of (0.1-1): 1, wherein in the Y203-ZrO2 powder, a weight ratio of a Y 2 0 3 powder to a ZrO2 powder is (3-5): 1, and drying the mixed powder to obtain a micron-sized mixed powder with a particle size of 1 to 50 m; (2) Cold spraying deposition of a protective coating for a plasma etching chamber: depositing the micron-sized mixed powder obtained at step (1) on an inner surface of a material of an etching chamber after being preheated by compressed air to obtain a protective coating for the plasma etching chamber, wherein during the cold spraying deposition, the compressed air serves as a working gas, a working gas temperature is 200 to 600°C, a working gas pressure is 1.5 to 3.0 MPa, and a spraying distance is 10 to 60 mm.
3. The preparation method of the protective coating for the IC equipment plasma etching chamber according to claim 1, characterized in that: a spraying apparatus for a protective coating for a plasma etching chamber comprises an air inlet pipe 1, a heater 2, a powder feeder 5, an electromagnetic valve 6, a supersonic nozzle 4, and a control cabinet 1, wherein one end of the air inlet pipe is connected to an air compressor, the other end of the air inlet pipe is connected to the powder feeder, the heater, and the supersonic nozzle, and a part, placed in the heater, of the air inlet pipe has a spiral structure.
4. The preparation method of the protective coating for the IC equipment plasma etching chamber according to claim 1, characterized in that: in the process of preparing a protective coating for a plasma etching chamber, a working gas output by the air compressor is divided into two parts, one part enters the heater, and then enters a mixing cavity of the supersonic nozzle after being preheated; the other part enters the powder feeder, and as a carrier gas, introduces a powder into the supersonic nozzle to be mixed with the first part of gas which is preheated; after instantaneously preheating the powder, the gas passes through a convergent-divergent region of the supersonic nozzle and expands and accelerates to form a supersonic gas-solid two-phase flow which impacts on an inner surface of a material of the etching chamber at a high speed to make the powder deform severely to realize deposition, and a composite protective coating is formed on the inner surface of the material of the etching chamber.
5. The preparation method of the protective coating for the IC equipment plasma etching chamber according to claim 4, characterized in that: a porosity of the protective coating is less than 2%, an interface bonding strength between a ceramic coating and a matrix material is 20 to 50 MPa, and a thickness of the coating is 10 to 400 [m.