Tantalum carbide composite coating with interpenetrating network structure as well as preparation method and application of tantalum carbide composite coating

Abstract

The invention discloses an interpenetrating network structure tantalum carbide composite coating as well as a preparation method and application thereof, and relates to the technical field of graphite materials. Comprising the following steps: 1, preparing a carbide coating with an interpenetrating network structure on a graphite substrate; 2, cleaning and drying the carbide coating with the interpenetrating network structure, mixing inorganic tantalum salt, alkane and hydrogen according to the molar ratio of (2-5): (2-5): (1-2) in an inert atmosphere by taking argon as carrier gas, and then carrying out CVD (Chemical Vapor Deposition) under the conditions that the pressure of the mixed gas is 5-100 mbar, the deposition temperature is 1000-1800 DEG C and the deposition time is 6-10 hours to obtain the interpenetrating network structure carbide coating. The yield of the TaC coating is improved, the binding force of the coating and a substrate material is improved, and cracking of the coating is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of crucibles, and in particular relates to an interpenetrating network structure tantalum carbide composite coating, a preparation method and an application thereof. Background Art

[0002] During the production of third-generation semiconductors SiC and GaN, existing SiC-coated graphite discs and BN-coated graphite discs react chemically with corrosive gases such as hydrogen and ammonia at high temperatures. This causes the graphite material to be exposed to air during the production process, and the impurities and corrosive gases in the graphite material damage the graphite material, thereby affecting the quality of crystal growth.

[0003] Tantalum carbide (TaC) ceramic is a material that maintains excellent mechanical properties in ultra-high temperatures above 3000°C. Its melting point can reach 3880°C, and it features high specific strength, oxidation resistance, and excellent ablation resistance. These characteristics enable TaC coatings to remain stable in harsh semiconductor environments, making it a coating material with great application prospects in third-generation semiconductor production.

[0004] Currently, there are many methods for preparing TaC coatings, such as CVD, sol-gel, and molten salt methods. However, these methods have limitations. For example, CVD requires a large amount of metal-organic gas as a reaction source, which is highly hazardous and expensive. Furthermore, TaC coatings prepared by molten salt and sol-gel methods exhibit weak bonding strength with the graphite substrate, resulting in a loose coating.

[0005] At present, among the preparation methods of tantalum carbide coating, the density and purity of the coating obtained by chemical vapor deposition (CVD) are the best, and it is the most commonly used preparation method. However, due to the high brittleness of tantalum carbide coating and the mismatch of thermal expansion coefficient with the substrate material, the coating prepared by conventional chemical vapor deposition is tightly stacked on the substrate surface. In a high-temperature growth environment, as the temperature rises, the thermal mismatch between the graphite substrate and the coating gradually increases, resulting in the generation of thermal stress between the two, which manifests itself in the form of cracks, thereby providing a channel for the growth atmosphere to erode the graphite substrate. With this position as the initial erosion point, the graphite substrate is gradually corroded, resulting in complete separation between the coating and the substrate, and protection failure. In addition, the conventional CVD method has a slow growth rate and is expensive. Although it is the main preparation method at present, the cost issue will also affect its large-scale promotion and use in single crystal growth. Summary of the Invention

[0006] The purpose of the present invention is to provide an interpenetrating network structure tantalum carbide composite coating, a preparation method and an application, aiming to effectively solve the problem that tantalum carbide coatings are prone to cracking. An attempt is made to prepare an interpenetrating network carbide transition layer between the tantalum carbide coating and the substrate, and then the tantalum carbide coating is deposited by chemical vapor deposition. This can not only improve the bonding strength of the tantalum carbide coating but also reduce the preparation cost.

[0007] In order to achieve the purpose of the present invention, on the one hand, the present invention provides a method for preparing an interpenetrating network structure tantalum carbide composite coating, comprising the following steps: Step 1: preparing an interpenetrating network structure carbide coating on a graphite substrate; Step 2: After cleaning and drying the interpenetrating network structure carbide coating, in an inert atmosphere, using argon as a carrier gas, inorganic tantalum salt, alkane and hydrogen are mixed in a molar ratio of (2-5): (2-5): (1-2), and then CVD deposition is performed. The pressure of the mixed gas is 5-100 mbar, the deposition temperature is 1000-1800 ° C, and the deposition time is 6-10 h.

[0008] In one possible embodiment, the alkane is selected from at least one of methane, ethane or propane.

[0009] In one possible implementation, during the CVD deposition process, a heating rate is 3-10° C. / min.

[0010] In one possible embodiment, the inorganic tantalum salt is selected from tantalum pentachloride.

[0011] In one possible implementation, the evaporation temperature of the inorganic tantalum salt is 250-600°C.

[0012] In a possible implementation, the carrier gas flow rate of the inorganic tantalum salt is 3-10 g / min, the alkane flow rate is 50-200 sccm, and the alkane carrier gas flow rate is 500-5000 sccm.

[0013] In one possible embodiment, the preparation method of the interpenetrating network structure carbide coating is: a suspension formed by mixing carbide particles, a binder and a solvent in proportion, or a suspension formed by mixing a metal element, a sintering aid, a binder and a solvent in proportion, is uniformly applied to the surface of the substrate; after drying, the suspension is vacuum sintered at 1200-2400°C for 2-4h to obtain the obtained product.

[0014] In one possible embodiment, the carbide particles are TaC; the particle size is 0.1-10 μm; the metal element is one of Ta, Co or Ni; the particle size of the metal element is 0.1-10 μm; the binder is selected from one or a combination of epoxy resin, silicone resin, graphite glue, phenolic resin, polyethylene glycol, polyvinyl alcohol, polyurethane, acrylate or polyvinyl chloride; the solvent is selected from one or a combination of deionized water, trichloroethylene, toluene, styrene, benzene, anhydrous ethanol, chloroform, acetone, triethanolamine or ethyl acetate; in the suspension, the mass percentage of carbide particles or metal element mixed powder is 50-80%, and the mass percentage of the binder is 1-20%.

[0015] On the other hand, the present application provides an interpenetrating network structure tantalum carbide composite coating, which is prepared by the above-mentioned preparation method of the interpenetrating network structure tantalum carbide composite coating, including an interpenetrating network structure tantalum carbide coating and a tantalum carbide dense layer, wherein the thickness of the interpenetrating network structure tantalum carbide coating is 30-50 μm, and the thickness of the tantalum carbide dense layer is 10-20 μm.

[0016] The present application also provides a composite substrate for preparing semiconductor materials, comprising a substrate, to which the above-mentioned interpenetrating network structure tantalum carbide composite layer structure is attached, wherein an interpenetrating network structure tantalum carbide coating is attached to the surface of the substrate, and a tantalum carbide dense layer is attached to the surface of the interpenetrating network structure tantalum carbide coating.

[0017] The present invention has achieved the following beneficial effects: The present application combines the advantages of CVD-TaC coating and interpenetrating network structure carbide coating, effectively reduces the preparation cost of TaC coating, improves the bonding strength of TaC coating, and can be mass-produced; An interpenetrating network structured tantalum carbide composite coating and its preparation method. This material comprises an interpenetrating network carbide structure layer and a dense tantalum carbide layer. The two layers are tightly bonded via chemical bonds, significantly enhancing the tantalum carbide coating's high-temperature corrosion resistance, reducing failures caused by coating cracks, and broadening the material's application range. Furthermore, the material's preparation process is simple, cost-effective, and suitable for industrial-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is the XRD pattern of Example 1 provided by the present invention. DETAILED DESCRIPTION

[0019] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0020] The tantalum carbide coating and its preparation method of the present invention are described below with reference to specific embodiments.

[0021] In Example 1, a high-purity graphite sheet was selected as the substrate material. The substrate had a diameter of 30 mm and a thickness of 10 mm. The substrate was ultrasonically cleaned in anhydrous ethanol for 10 min and then dried with nitrogen purge. Weigh 25 g of TaC powder with a particle size of 0.1-10 μm, 1 g of Co powder with a particle size of 0.1-10 μm, 20 ml of anhydrous ethanol, and 2 g of epoxy resin, mix them, and ultrasonicate for 5 min to obtain a suspension, which is then allowed to stand for use.

[0022] The suspension is evenly coated on the surface of the substrate, and then placed in an oven for drying for 10 hours, and then placed in a vacuum environment and dried at 200°C for 10 hours. The dried substrate is sintered in a vacuum at a sintering temperature of 1800°C for 2 hours, and naturally cooled after sintering to obtain a layer of interpenetrating network structure carbide coating with uniform thickness.

[0023] The sintered substrate material is placed in a CVD reaction chamber, and the mechanical pump is turned on to pump the pressure in the chamber to below 1 mbar, and then the reaction chamber is heated to 1500 °C.

[0024] The tantalum pentachloride evaporation chamber was heated to 300°C and held for 30 minutes. Argon, a carrier gas at a flow rate of 2000 sccm, was then delivered to the reaction chamber. Methane and hydrogen were simultaneously introduced using argon as the carrier gas. The argon flow rate for the tantalum pentachloride was 1000 sccm, while the methane and hydrogen flows were both 1000 sccm. The methane flow rate was 200 sccm, and the hydrogen flow rate was 400 sccm. The tantalum pentachloride flow rate was adjusted by the carrier gas flow rate and the evaporation chamber room temperature. After the gases were uniformly mixed in the reaction chamber, they were deposited on the interpenetrating network carbide coating for 6 hours to obtain an interpenetrating network tantalum carbide composite coating.

[0025] Turn off the heating power and wait for the vapor deposition equipment to cool down. Once the temperature drops below 100°C, turn on the vacuum pump to exhaust the gas in the reaction chamber into the exhaust treatment device until the vacuum level drops below 1 mbar. Then turn off the vacuum pump and introduce argon. Once the reaction chamber pressure returns to ambient pressure, open the chamber and remove the prepared graphite sheet composite substrate with an interpenetrating network structured tantalum carbide composite coating.

[0026] The thickness of the interpenetrating network structure tantalum carbide coating is 30-50 μm, and the thickness of the tantalum carbide dense layer is 10-20 μm.

[0027] In Example 2, a high-purity graphite sheet was selected as the substrate material. The substrate had a diameter of 30 mm and a thickness of 10 mm. The substrate was ultrasonically cleaned in anhydrous ethanol for 10 min and then dried with nitrogen purge. Weigh 25 g of TaC powder with a particle size of 0.1-10 μm, 1 g of Co powder with a particle size of 0.1-10 μm, 20 ml of acetone, and 2 g of phenolic resin, mix them, and ultrasonicate for 5 minutes to obtain a suspension, which is then allowed to stand for use.

[0028] The suspension is evenly coated on the surface of the substrate, and then placed in an oven for drying for 10 hours, and then placed in a vacuum environment and dried at 200°C for 10 hours. The dried substrate is sintered in a vacuum at a sintering temperature of 1800°C for 2 hours, and naturally cooled after sintering to obtain a layer of interpenetrating network structure carbide coating with uniform thickness.

[0029] The sintered substrate material is placed in a CVD reaction chamber, and the mechanical pump is turned on to pump the pressure in the chamber to below 1 mbar, and then the reaction chamber is heated to 1500 °C.

[0030] The tantalum pentachloride evaporation chamber was heated to 300°C and held for 30 minutes. Argon, a carrier gas at a flow rate of 2000 sccm, was then delivered to the reaction chamber. Methane and hydrogen were simultaneously introduced using argon as the carrier gas. The argon flow rate for the tantalum pentachloride was 1000 sccm, while the methane and hydrogen flows were both 1000 sccm. The methane flow rate was 200 sccm, and the hydrogen flow rate was 400 sccm. The tantalum pentachloride flow rate was adjusted by the carrier gas flow rate and the evaporation chamber room temperature. After the gases were uniformly mixed in the reaction chamber, they were deposited on the interpenetrating network carbide coating for 8 hours to obtain an interpenetrating network tantalum carbide composite coating.

[0031] Turn off the heating power and wait for the vapor deposition equipment to cool down. Once the temperature drops below 100°C, turn on the vacuum pump to exhaust the gas in the reaction chamber into the exhaust treatment device until the vacuum level drops below 1 mbar. Then turn off the vacuum pump and introduce argon. Once the reaction chamber pressure returns to ambient pressure, open the chamber and remove the prepared graphite sheet composite substrate with an interpenetrating network structured tantalum carbide composite coating.

[0032] The thickness of the interpenetrating network structure tantalum carbide coating is 30-50 μm, and the thickness of the tantalum carbide dense layer is 10-20 μm.

[0033] In Example 3, a high-purity graphite sheet was selected as the substrate material. The substrate had a diameter of 30 mm and a thickness of 10 mm. The substrate was ultrasonically cleaned in anhydrous ethanol for 10 min and then dried with nitrogen purge. Weigh 25 g of TaC powder with a particle size of 0.1-10 μm, 1 g of Co powder with a particle size of 0.1-10 μm, 15 ml of ethyl acetate, and 5 g of graphite gel, mix them, and ultrasonicate for 5 min to obtain a suspension, which is then allowed to stand for use.

[0034] The suspension is evenly coated on the surface of the substrate, and then placed in an oven for drying for 10 hours, and then placed in a vacuum environment and dried at 200°C for 10 hours. The dried substrate is sintered in a vacuum at a sintering temperature of 1800°C for 2 hours, and naturally cooled after sintering to obtain a layer of interpenetrating network structure carbide coating with uniform thickness.

[0035] The sintered substrate material is placed in a CVD reaction chamber, and the mechanical pump is turned on to pump the pressure in the chamber to below 1 mbar, and then the reaction chamber is heated to 1500 °C.

[0036] The tantalum pentachloride evaporation chamber was heated to 300°C and held for 30 minutes. Argon, a carrier gas at a flow rate of 2000 sccm, was then delivered to the reaction chamber. Methane and hydrogen were simultaneously introduced using argon as the carrier gas. The argon flow rate for the tantalum pentachloride was 1000 sccm, while the methane and hydrogen flows were both 1000 sccm. The methane flow rate was 200 sccm, and the hydrogen flow rate was 400 sccm. The tantalum pentachloride flow rate was adjusted by the carrier gas flow rate and the evaporation chamber room temperature. After the gases were uniformly mixed in the reaction chamber, they were deposited on the interpenetrating network carbide coating for 10 hours to obtain an interpenetrating network tantalum carbide composite coating.

[0037] Turn off the heating power and wait for the vapor deposition equipment to cool down. Once the temperature drops below 100°C, turn on the vacuum pump to exhaust the gas in the reaction chamber into the exhaust treatment device until the vacuum level drops below 1 mbar. Then turn off the vacuum pump and introduce argon. Once the reaction chamber pressure returns to ambient pressure, open the chamber and remove the prepared graphite sheet composite substrate with an interpenetrating network structured tantalum carbide composite coating.

[0038] The thickness of the interpenetrating network structure tantalum carbide coating is 30-50 μm, and the thickness of the tantalum carbide dense layer is 10-20 μm.

[0039] The above-described embodiments merely illustrate several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that variations and improvements are possible without departing from the scope of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A method for preparing an interpenetrating network structure tantalum carbide composite coating, characterized in that: The steps include: Step 1: preparing an interpenetrating network structure carbide coating on a graphite substrate; Step 2: After cleaning and drying the interpenetrating network structure carbide coating, in an inert atmosphere, using argon as a carrier gas, inorganic tantalum salt, alkane and hydrogen are mixed in a molar ratio of (2-5): (2-5): (1-2), and then CVD deposition is performed. The pressure of the mixed gas is 5-100 mbar, the deposition temperature is 1000-1800 ° C, and the deposition time is 6-10 h.

2. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 1, characterized in that: The alkane is selected from at least one of methane, ethane or propane.

3. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 1, characterized in that: During the CVD deposition process, the heating rate is 3-10° C. / min.

4. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 1, characterized in that: The inorganic tantalum salt is selected from tantalum pentachloride.

5. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 1, characterized in that: The evaporation temperature of the inorganic tantalum salt is 250-600°C.

6. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 1, characterized in that: The carrier gas flow rate of the inorganic tantalum salt is 3-10 g / min, the alkane flow rate is 50-200 sccm, and the alkane carrier gas flow rate is 500-5000 sccm.

7. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 1, characterized in that: The preparation method of the interpenetrating network structure carbide coating is as follows: a suspension formed by mixing carbide particles, a binder and a solvent in proportion, or a suspension formed by mixing a metal element, a sintering aid, a binder and a solvent in proportion, is uniformly applied to the surface of a substrate; after drying, the suspension is vacuum sintered at 1200-2400°C for 2-4 hours to obtain the coating.

8. The method for preparing an interpenetrating network structure tantalum carbide composite coating according to claim 7, characterized in that: The carbide particles are TaC; the particle size is 0.1-10 μm; the metal element is one of Ta, Co or Ni; the particle size of the metal element is 0.1-10 μm; the binder is selected from one or a combination of epoxy resin, silicone resin, graphite glue, phenolic resin, polyethylene glycol, polyvinyl alcohol, polyurethane, acrylate or polyvinyl chloride; the solvent is selected from one or a combination of deionized water, trichloroethylene, toluene, styrene, benzene, anhydrous ethanol, chloroform, acetone, triethanolamine or ethyl acetate; in the suspension, the mass percentage of carbide particles or metal element mixed powder is 50-80%, and the mass percentage of the binder is 1-20%.

9. An interpenetrating network structure tantalum carbide composite coating, characterized in that: The invention relates to a composite coating of tantalum carbide with an interpenetrating network structure, prepared by the preparation method of any one of claims 1 to 8, comprising an interpenetrating network structure tantalum carbide coating and a tantalum carbide dense layer, wherein the thickness of the interpenetrating network structure tantalum carbide coating is 30-50 μm, and the thickness of the tantalum carbide dense layer is 10-20 μm.

10. A composite substrate for preparing semiconductor materials, characterized in that: The invention comprises a substrate, to which the interpenetrating network structure tantalum carbide composite layer structure according to claim 9 is attached, wherein an interpenetrating network structure tantalum carbide coating is attached to the surface of the substrate, and a tantalum carbide dense layer is attached to the surface of the interpenetrating network structure tantalum carbide coating.

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