A method for preparing a high-voltage insulation coating suitable for a semiconductor compact structure

Abstract

The application belongs to the field of material preparation, and particularly relates to a preparation method of a high-voltage-resistant insulation coating suitable for a semiconductor dense structure, comprising the following steps: pretreatment of a semiconductor substrate; ceramic powder prepared by using nanoscale raw materials to obtain first raw materials; granulation of the first raw materials, and plasma sintering of the granulated first raw materials to obtain second raw materials; particle size grading of the second raw materials to obtain third raw materials; and preparation of the high-voltage-resistant insulation coating suitable for the semiconductor dense structure on the pretreated semiconductor substrate by using the third raw materials through a plasma spraying process. The application uses nanoscale raw materials to effectively improve the high-temperature service stability of the coating. The combination strength and service life of the insulation coating are improved by granulation, sintering and particle size grading of the raw materials, the coating can work for a long time under an extra-high voltage working condition, and the service temperature and toughness of the coating are improved through the plasma spraying process.

Description

Technical Field

[0001] This invention belongs to the field of materials preparation, specifically relating to a method for preparing a high-voltage insulating coating suitable for dense semiconductor structures. Background Technology

[0002] Insulating coatings are coatings with excellent electrical insulation properties. They form a ceramic coating on the surface of the coated object with high volume resistivity, capable of withstanding strong electric fields without breakdown. This coating possesses high mechanical strength and good chemical stability, resisting aging, water, and chemical corrosion, while also exhibiting resistance to mechanical and thermal shock. These properties make insulating coatings widely used in electronics, power, communications, aerospace, and other fields to protect circuits and equipment from harsh environments such as high voltage, high temperature, and high humidity, thereby improving the safety and reliability of circuits and equipment.

[0003] Ceramic insulating coatings can effectively improve the production efficiency and operational safety of advanced manufacturing processes. Ceramic-based insulating coatings possess advantages such as high voltage resistance and high insulation, and are widely used in backplanes and critical insulation components in advanced semiconductor processes. They withstand temperature differences of 300-500°C and high voltage, making them one of the most demanding types of ceramic insulating coatings currently available. With the development of advanced semiconductor processes, higher performance requirements are being placed on ceramic insulating coatings. Long-term service withstand voltages of up to 2500 volts are required, along with the ability to withstand frequent temperature variations of 300-500°C. Therefore, smaller porosity, higher bonding strength, and resistance to high-voltage breakdown are necessary.

[0004] Conventional ceramic-based insulating coatings are typically prepared using micron-sized powders as raw materials. However, the materials often contain impurities such as Fe₂O₃, SiO₂, Al₂O₃, and CaO, with a content ≥0.5%. During coating preparation, the large particle size and uneven distribution of the powder result in numerous interconnected pore defects within the coating, leading to low bonding strength and service life. Furthermore, the presence of impurities such as Fe₂O₃, SiO₂, Al₂O₃, and CaO makes the coating highly susceptible to breakdown and sintering under prolonged operation at 2500 volts, ultimately causing cracking and failure. Summary of the Invention

[0005] (I) Purpose of the Invention

[0006] The purpose of this invention is to provide a method for preparing a high-voltage insulating coating suitable for dense semiconductor structures that can improve the bonding strength and lifespan of the insulating coating and can work for a long time under ultra-high voltage conditions.

[0007] (II) Technical Solution

[0008] To address the above problems, this invention provides a method for preparing a high-voltage insulating coating suitable for dense semiconductor structures, comprising the following steps:

[0009] Step 100: Pre-treat the semiconductor substrate;

[0010] Step 200: Prepare ceramic powder using nanoscale raw materials to obtain the first raw material;

[0011] Step 300: Granulate the first raw material and then perform plasma sintering on the granulated first raw material to obtain the second raw material;

[0012] Step 400: Perform particle size distribution on the second raw material to obtain the third raw material;

[0013] Step 500: On the pretreated semiconductor substrate, a high-voltage insulating coating suitable for dense semiconductor structures is prepared by plasma spraying using the third raw material.

[0014] In another aspect of the present invention, preferably, the thickness of the insulating coating is 0.25 mm to 0.39 mm.

[0015] In another aspect of the present invention, preferably, the stress range of the insulating coating is 20 to 40 MPa.

[0016] In another aspect of the present invention, preferably, the insulating coating includes at least a base layer, an intermediate layer, and a surface layer; the base layer covers the surface of the semiconductor substrate, and the intermediate layer is disposed between the base layer and the surface layer; the third raw material includes a base layer raw material, an intermediate layer raw material, and a surface layer raw material.

[0017] In step 500, preparing a high-voltage insulating coating suitable for dense semiconductor structures on the pretreated semiconductor substrate using the third raw material via plasma spraying includes:

[0018] A substrate layer is prepared on the surface of the semiconductor substrate using substrate layer raw materials based on the first parameters of the plasma spraying process.

[0019] After a preset first time, an intermediate layer is prepared on the base layer using the intermediate layer material through the second parameters of the plasma spraying process;

[0020] After a preset second time, a surface layer is prepared on the intermediate layer using the surface layer material through the third parameter of the plasma spraying process.

[0021] In another aspect of the present invention, preferably, the thickness of the base layer is 0.12 to 0.2 mm, the thickness of the intermediate layer is 0.12 to 0.2 mm, and the thickness of the surface layer is 0.01 to 0.1 mm.

[0022] In another aspect of the present invention, preferably, the purity of the base layer raw material is ≥99.5%; the purity of the intermediate layer raw material is ≥99.99%; and the purity of the surface layer raw material is ≥99.999%.

[0023] In another aspect of the present invention, preferably, the porosity of the coating is 1 to 5%; the porosity of the base layer is 3 to 5%; the porosity of the intermediate layer is 1 to 3%; and the porosity of the surface layer is less than or equal to 1%.

[0024] In another aspect of the present invention, preferably, the process parameters of the plasma sintering include: power: 40-50 kW; temperature: 10000-30000 °C; and sintering time within 0.5 seconds.

[0025] In another aspect of the present invention, preferably, the first parameters of the plasma spraying process include: power of 45-50 kW; powder feeding rate of 40-50 g / min; and spraying distance of 100-120 mm.

[0026] The second parameters of the plasma spraying process include: power of 40-45Kw; powder feeding rate of 15-30g / min; and spraying distance of 100-110mm.

[0027] The third parameter of the plasma spraying process includes: power of 40-42 kW; powder feeding rate of 5-10 g / min; and spraying distance of 90-100 mm.

[0028] In another aspect of the present invention, preferably, the plasma spraying process is carried out in an atmospheric, low-pressure, or inert gas protected environment.

[0029] In another aspect of the present invention, preferably, the components of the base layer material, the intermediate layer material and the surface layer material respectively include one or more of alumina, zirconium oxide, yttrium oxide, dysprosium oxide, ytterbium oxide, gadolinium oxide, lanthanum oxide, cerium oxide and magnesium oxide.

[0030] (III) Beneficial Effects

[0031] The above-described technical solution of the present invention has the following beneficial technical effects:

[0032] This invention utilizes nanoscale raw materials, effectively enhancing the high-temperature service stability of the coating. By granulating, sintering, and adjusting the particle size distribution of the raw materials, the bonding strength and lifespan of the insulating coating are improved, enabling it to operate for extended periods under ultra-high voltage conditions. Furthermore, the plasma spraying process enhances the coating's operating temperature and toughness. The high-energy plasma spraying process ensures efficient and stable production, guaranteeing complete powder melting to form a dense coating. This coating features uniform and controllable pore size, high bonding strength, and a simple process. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the bimodal particle size distribution of ceramic powder according to an embodiment of the present invention;

[0034] Figure 2 This is a schematic diagram of the semiconductor substrate surface according to an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the cross-sectional morphology of the insulating coating according to an embodiment of the present invention;

[0036] Figure 4 This is a partial schematic diagram of a 2500-volt test of the insulating coating according to an embodiment of the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0038] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0039] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] Example

[0042] A method for preparing a high-voltage insulating coating suitable for dense semiconductor structures includes the following steps:

[0043] Step 100: Pretreatment of the semiconductor substrate; the specific details of the semiconductor substrate are not limited here. Figure 2 A schematic diagram of a semiconductor substrate surface according to an embodiment of the present invention is shown, as follows: Figure 2 As shown, the semiconductor substrate in this embodiment is a workpiece with a specific pattern etched by laser on its surface; the specific content of the pretreatment of the semiconductor substrate is not limited here. Optionally, in this embodiment, the surface of the semiconductor substrate can be cleaned, which can be laser cleaning or ion cleaning.

[0044] Step 200: Obtain the first raw material by preparing ceramic powder from nanoscale raw materials; the specific content of the ceramic powder is not limited here. Optionally, in this embodiment, the ceramic powder may include one or more of alumina, zirconium oxide, yttrium oxide, dysprosium oxide, ytterbium oxide, gadolinium oxide, lanthanum oxide, cerium oxide, and magnesium oxide; furthermore, in this embodiment, the primary particle size of the nanoscale raw material is 5-25 nm, and its typical particle size is 5-15 nm; the particle size of the first raw material is less than 45 μm;

[0045] Step 300: Granulate the first raw material and then perform plasma sintering on the granulated first raw material to obtain the second raw material; the specific steps of plasma sintering are not limited here. Optionally, in this embodiment, the process parameters of plasma sintering include power: 40-50Kw; temperature: 10000-30000℃; sintering time within 0.5S.

[0046] Step 400: Perform particle size distribution on the second raw material to obtain the third raw material; Figure 1 A schematic diagram of the bimodal particle size distribution of ceramic powder according to an embodiment of the present invention is shown; as follows: Figure 1 As shown, the third raw material has a single-peak particle size distribution characteristic; the peak value of the medium particle size of the third raw material is 5-30 μm, and the typical particle size distribution ratio is 70%-90 wt% for medium particle size powder and 10-30 wt% for fine and coarse powder.

[0047] Step 500: On the pretreated semiconductor substrate, a high-voltage insulating coating suitable for dense semiconductor structures is prepared by plasma spraying using the third raw material; optionally, in this embodiment, the thickness of the coating in step 500 is 0.25mm to 0.39mm; further, the stress range of the coating in step 500 is 20 to 40MPa. The specific content of the plasma spraying is not limited here. Optionally, in this embodiment, the parameters of the plasma spraying process include a power of 40 to 50 kW; a powder feeding rate of 5-50 g / min; a spraying distance of 90-120 mm; and the spraying environment of the plasma spraying process is one of atmospheric, low-pressure, or inert gas protective environments.

[0048] This invention utilizes nanoscale raw materials, effectively enhancing the high-temperature service stability of the coating. By granulating, sintering, and adjusting the particle size distribution of the raw materials, the bonding strength and lifespan of the insulating coating are improved, enabling it to operate for extended periods under ultra-high voltage conditions. Furthermore, the plasma spraying process enhances the coating's operating temperature and toughness. The high-energy plasma spraying process ensures efficient and stable production, guaranteeing complete powder melting to form a dense coating. This coating features uniform and controllable pore size, high bonding strength, and a simple process.

[0049] In one embodiment of the present invention, the insulating coating further comprises at least a base layer, an intermediate layer, and a surface layer; the base layer covers the surface of the semiconductor substrate, and the intermediate layer is disposed between the base layer and the surface layer; the third raw material comprises a base layer raw material, an intermediate layer raw material, and a surface layer raw material.

[0050] In step 500, preparing a high-voltage insulating coating suitable for dense semiconductor structures on the pretreated semiconductor substrate using the third raw material via plasma spraying includes:

[0051] A substrate layer is prepared on the surface of the semiconductor substrate using substrate layer raw materials based on the first parameters of the plasma spraying process.

[0052] An intermediate layer is prepared on the substrate layer using intermediate layer raw materials through the second parameter of the plasma spraying process;

[0053] A surface layer is prepared on the intermediate layer using surface layer raw materials through the third parameter of the plasma spraying process.

[0054] The thickness of the base layer is 0.12–0.2 mm, the thickness of the intermediate layer is 0.12–0.2 mm, and the thickness of the surface layer is 0.01–0.1 mm.

[0055] The purity of the base layer material is ≥99.5%; the purity of the intermediate layer material is ≥99.99%; and the purity of the surface layer material is ≥99.999%. The specific contents of the base layer material, intermediate layer material, and surface layer material are not limited here; they can be the same raw material or different raw materials. The components of the base layer material, intermediate layer material, and surface layer material respectively include one or more of the following: alumina, zirconium oxide, yttrium oxide, dysprosium oxide, ytterbium oxide, gadolinium oxide, lanthanum oxide, cerium oxide, and magnesium oxide.

[0056] A base layer is first sprayed onto the surface of the semiconductor substrate using a plasma spraying process, followed by an intermediate layer sprayed onto the surface of the base layer; then a surface layer is sprayed onto the surface of the intermediate layer; the porosity of the coating is 1-5%; the porosity of the base layer is 3-5%, the porosity of the intermediate layer is 1-3%, and the porosity of the surface layer is less than or equal to 1%.

[0057] The first parameters of the plasma spraying process include: power of 45-50Kw; powder feeding rate of 40-50g / min; and spraying distance of 100-120mm.

[0058] The second parameters of the plasma spraying process include: power of 40-45Kw; powder feeding rate of 15-30g / min; and spraying distance of 100-110mm.

[0059] The third parameter of the plasma spraying process includes: power of 40-42 kW; powder feeding rate of 5-10 g / min; and spraying distance of 90-100 mm.

[0060] This embodiment employs a three-layer coating structure to further improve the bonding strength and lifespan of the insulating coating, enabling it to operate for extended periods under ultra-high voltage conditions. Furthermore, plasma spraying enhances the coating's operating temperature and toughness. The layers complement each other, improving overall weather resistance; the base layer strengthens adhesion, while the surface coating forms a dense insulating layer.

[0061] In one embodiment of the present invention, the preparation method further includes sealing the coating. The sealing step includes:

[0062] The semiconductor component to be sealed is placed in a sealed container.

[0063] Add sealing agent to the sealed container and fill the entire container with sealing agent.

[0064] Control the sealed container to a negative pressure state so that the sealing agent flows into the pores inside the coating of the semiconductor component;

[0065] Drain the sealing agent from the sealed container and clean the semiconductor components;

[0066] The sealing agent inside the semiconductor component is remelted, and after remelting, it solidifies and fills the pores inside the coating of the semiconductor component.

[0067] This embodiment can optimize the inherent porosity defects inside the coating, maintaining good performance and service life in harsh environments.

[0068] Example 1

[0069] Laser cleaning of semiconductor substrate; ceramic powder prepared from nano-sized alumina raw material; the primary particle size of the nano-sized raw material is 5-25 nm, with a typical particle size of 5-15 nm; particle size less than 45 μm; obtaining a first raw material; granulating the first raw material and then plasma sintering the granulated first raw material to obtain a second raw material; the process parameters for plasma sintering include power: 40 kW; temperature: 10000℃; sintering time within 0.5 s; particle size distribution of the second raw material to obtain a third raw material; the third raw material has a medium particle size peak of 5-30 μm, and a typical particle size distribution ratio is 70% wt% medium particle size powder and 30 wt% fine and coarse powder; utilizing the... The third raw material is used to prepare a high-voltage insulating coating suitable for dense semiconductor structures via plasma spraying. The third raw material consists of a base layer of zirconium oxide with a purity ≥99.5%, an intermediate layer of cerium oxide with a purity ≥99.99%, and a surface layer of lanthanum oxide with a purity ≥99.999%. The first parameters of the plasma spraying process include: power of 45 kW, powder feed rate of 40 g / min, and spraying distance of 100 mm. The second parameters include: power of 40 kW, powder feed rate of 15 g / min, and spraying distance of 100 mm. The third parameters include: power of 40 kW, powder feed rate of 5 g / min, and spraying distance of 90 mm. The spraying environment for the plasma spraying process is atmospheric. The base layer thickness is 0.12 mm, the intermediate layer thickness is 0.12 mm, the surface layer thickness is 0.01 mm, and the total coating thickness is 0.25 mm.

[0070] Example 2

[0071] Laser cleaning of semiconductor substrate; ceramic powder prepared from nano-sized magnesium oxide raw material; the primary particle size of the nano-sized raw material is 5-25 nm, with a typical particle size of 5-15 nm; particle size less than 45 μm; obtaining a first raw material; granulating the first raw material and then plasma sintering the granulated first raw material to obtain a second raw material; the process parameters for plasma sintering include power: 50 kW; temperature: 30000℃; sintering time within 0.5 s; particle size distribution of the second raw material to obtain a third raw material; the third raw material has a medium particle size peak of 5-30 μm, and a typical particle size distribution ratio is 90% wt% medium particle size powder and 10 wt% fine and coarse powder; utilizing the... The third raw material is used to prepare a high-voltage insulating coating suitable for dense semiconductor structures via plasma spraying. The base layer material is magnesium oxide with a purity ≥99.5%, the intermediate layer material is aluminum oxide with a purity ≥99.99%, and the surface layer material is aluminum oxide with a purity ≥99.999%. The first parameters of the plasma spraying process include: power of 50 kW, powder feeding rate of 50 g / min, and spraying distance of 120 mm. The second parameters include: power of 45 kW, powder feeding rate of 30 g / min, and spraying distance of 110 mm. The third parameters include: power of 42 kW, powder feeding rate of 10 g / min, and spraying distance of 100 mm. The base layer thickness is 0.2 mm, the intermediate layer thickness is 0.15 mm, the surface layer thickness is 0.04 mm, and the total coating thickness is 0.39 mm.

[0072] Example 3

[0073] Laser cleaning of semiconductor substrate; ceramic powder prepared from nano-sized cerium oxide raw material; the primary particle size of the nano-sized raw material is 5-25 nm, with a typical particle size of 5-15 nm; particle size less than 45 μm; obtaining a first raw material; granulating the first raw material and then plasma sintering the granulated first raw material to obtain a second raw material; the process parameters for plasma sintering include power: 45 kW; temperature: 20000℃; sintering time within 0.5 s; particle size distribution of the second raw material to obtain a third raw material; the third raw material has a medium particle size peak of 5-30 μm, and a typical particle size distribution ratio is 80% wt% medium particle size powder and 20 wt% fine and coarse powder; utilizing the... The third raw material is used to prepare a high-voltage insulating coating suitable for dense semiconductor structures via plasma spraying. The base layer material is alumina with a purity ≥99.5%, the intermediate layer material is alumina with a purity ≥99.99%, and the surface layer material is alumina with a purity ≥99.999%. The first parameters of the plasma spraying process include: power of 47 kW, powder feed rate of 45 g / min, and spraying distance of 110 mm. The second parameters include: power of 43 kW, powder feed rate of 25 g / min, and spraying distance of 105 mm. The third parameters include: power of 41 kW, powder feed rate of 7 g / min, and spraying distance of 80 mm. The base layer thickness is 0.08 mm, the intermediate layer thickness is 0.2 mm, the surface layer thickness is 0.1 mm, and the total coating thickness is 0.38 mm. Figure 3 A schematic diagram of the cross-sectional morphology of the insulating coating in this embodiment is shown.

[0074] Comparative Example

[0075] The semiconductor substrate is laser-cleaned; ceramic powder is prepared from nano-sized alumina raw materials; a coating is prepared by plasma spraying process; the parameters of the plasma spraying process include a power of 40 kW, a powder feeding rate of 5 g / min, and a spraying distance of 80 mm; the spraying environment of the plasma spraying process is atmospheric, and the thickness of the entire coating is 0.4 mm.

[0076] The experimental results of Examples 1-3 and the comparative examples are shown in Table 1.

[0077] Test results of Examples 1-3 and Comparative Examples

[0078]

[0079] In summary, this invention utilizes nanoscale raw materials, effectively enhancing the high-temperature service stability of the coating. Granulation, sintering, and particle size distribution of the raw materials improve the bonding strength and lifespan of the insulating coating, enabling it to operate for extended periods under ultra-high voltage conditions. Furthermore, plasma spraying enhances the coating's operating temperature and toughness. The high-energy plasma spraying process ensures efficient and stable production, guaranteeing complete powder melting to form a dense coating. This results in a uniform and controllable pore size in the insulating coating, high bonding strength, and a simple process.

[0080] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the invention should be included within the protection scope of the invention. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

[0081] The present invention has been described above with reference to embodiments thereof. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. The scope of the invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

[0082] Although embodiments of the present invention have been described in detail, it should be understood that various changes, substitutions, and modifications can be made to the embodiments of the present invention without departing from the spirit and scope of the invention.

[0083] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a high-voltage insulating coating suitable for dense semiconductor structures, characterized in that, Includes the following steps: Step 100: Pre-treat the semiconductor substrate; Step 200: Prepare ceramic powder using nanoscale raw materials to obtain the first raw material; Step 300: Granulate the first raw material and then perform plasma sintering on the granulated first raw material to obtain the second raw material; Step 400: Perform particle size distribution on the second raw material to obtain the third raw material; Step 500: On the pretreated semiconductor substrate, a high-voltage insulating coating suitable for dense semiconductor structures is prepared by plasma spraying using the third raw material; The insulating coating comprises at least a base layer, an intermediate layer, and a surface layer; the base layer covers the surface of the semiconductor substrate, and the intermediate layer is disposed between the base layer and the surface layer; the third raw material comprises a base layer raw material, an intermediate layer raw material, and a surface layer raw material. In step 500, preparing a high-voltage insulating coating suitable for dense semiconductor structures on the pretreated semiconductor substrate using the third raw material via plasma spraying includes: A substrate layer is prepared on the surface of the semiconductor substrate using substrate layer raw materials based on the first parameters of the plasma spraying process. An intermediate layer is prepared on the substrate layer using intermediate layer raw materials through the second parameter of the plasma spraying process; A surface layer is prepared on the intermediate layer using surface layer raw materials through the third parameter of the plasma spraying process.

2. The preparation method according to claim 1, characterized in that, The thickness of the insulating coating is 0.25 mm to 0.39 mm.

3. The preparation method according to claim 1, characterized in that, The stress range of the insulating coating is 20–40 MPa.

4. The preparation method according to claim 1, characterized in that, The thickness of the base layer is 0.12–0.2 mm, the thickness of the intermediate layer is 0.12–0.2 mm, and the thickness of the surface layer is 0.01–0.1 mm; the purity of the base layer raw material is ≥99.5%; the purity of the intermediate layer raw material is ≥99.99%; and the purity of the surface layer raw material is ≥99.999%.

5. The preparation method according to claim 1, characterized in that, The porosity of the coating is 1-5%; the porosity of the base layer is 3-5%; the porosity of the intermediate layer is 1-3%; and the porosity of the surface layer is less than or equal to 1%.

6. The preparation method according to claim 1, characterized in that, The process parameters for plasma sintering include: power: 40-50 kW; temperature: 10000-30000 °C; and sintering time within 0.5 seconds.

7. The preparation method according to claim 1, characterized in that, The first parameters of the plasma spraying process include: power of 45-50Kw; powder feeding rate of 40-50g / min; and spraying distance of 100-120mm. The second parameters of the plasma spraying process include: power of 40-45Kw; powder feeding rate of 15-30g / min; and spraying distance of 100-110mm. The third parameter of the plasma spraying process includes: power of 40-42 kW; powder feeding rate of 5-10 g / min; and spraying distance of 90-100 mm.

8. The preparation method according to claim 1, characterized in that, The plasma spraying process is carried out in an atmospheric, low-pressure, or inert gas protected environment.

9. The preparation method according to claim 1, characterized in that, The base layer material, intermediate layer material, and surface layer material are composed of one or more of the following: alumina, zirconium oxide, yttrium oxide, dysprosium oxide, ytterbium oxide, gadolinium oxide, lanthanum oxide, cerium oxide, and magnesium oxide.

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