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CN-121974702-A - Silicon carbide ceramic material with low volume resistivity and preparation method thereof

CN121974702ACN 121974702 ACN121974702 ACN 121974702ACN-121974702-A

Abstract

The invention relates to the field of functional ceramics, and provides a silicon carbide ceramic material with low volume resistivity and a preparation method thereof, which are used for reducing the volume resistivity of silicon carbide ceramic and meeting the use requirement of semiconductor etching equipment; and finally, placing the silicon carbide ring with exposed inner and outer surface graphite in a graphite oxidation furnace, and obtaining the silicon carbide ceramic material with low volume resistivity after treatment, thereby ensuring the overall compactness, thermal conductivity and bending strength of the material, reducing the volume resistivity of the silicon carbide ceramic and being convenient for being applied to etching equipment.

Inventors

  • CHEN JUNHUA
  • CHENG DONGYUAN
  • HAN CHAOYANG
  • XIE SHENGQIANG
  • LI JINGRU

Assignees

  • 浙江富乐德半导体材料科技有限公司

Dates

Publication Date
20260505
Application Date
20251010

Claims (10)

  1. 1. A preparation method of a silicon carbide ceramic material with low volume resistivity is characterized by comprising the following steps: (1) Placing a graphite substrate in a CVD furnace, vacuumizing the CVD furnace, re-pressing to the atmospheric pressure, introducing process gas, preserving heat for 50-60h to obtain a CVD-SiC ceramic material, cooling to room temperature, and discharging; (2) Annealing the silicon carbide ring prepared in the step (1); (3) Processing the inner and outer walls of the silicon carbide annular material obtained in the step (2); (4) And (3) placing the silicon carbide ring exposed out of the inner and outer diameter graphite in the step (3) in a graphite oxidation furnace, and processing to obtain the silicon carbide ceramic material with low volume resistivity.
  2. 2. The method of producing a low volume resistivity silicon carbide ceramic material according to claim 1, wherein the graphite substrate of step (1) is selected from the group consisting of annular graphite substrates.
  3. 3. The method for producing a low-volume resistivity silicon carbide ceramic material according to claim 1, wherein the vacuum degree in the step (1) is controlled to be 10 -4 Pa or less, and the holding time is not less than 15 minutes.
  4. 4. The method for preparing the silicon carbide ceramic material with low volume resistivity according to claim 1, wherein the vacuum post-repressing process is to heat up to 1500-1650 ℃ at a heating rate of 0.1-3 ℃ per minute.
  5. 5. The method of claim 1, wherein the process gas comprises a trichlorosilane gas, hydrogen, and nitrogen.
  6. 6. The method of producing a low volume resistivity silicon carbide ceramic material as claimed in claim 1 or 5, wherein the purity of the trichlorosilane gas is >98%, the purity of the hydrogen gas is >99.996%, and the purity of the nitrogen gas is >99.999%.
  7. 7. The method for preparing the low-volume-resistivity silicon carbide ceramic material according to claim 1, wherein in the annealing treatment process in the step (2), a silicon carbide ring is placed in an annealing furnace, the temperature is raised to be kept for 4-6 h in an argon atmosphere at the temperature of 1900-2200 ℃ at the temperature rising rate of 0.1-0.5 ℃ per minute, and then the silicon carbide ring is naturally cooled to room temperature along with the furnace when the temperature is lowered.
  8. 8. The method of producing a low volume resistivity silicon carbide ceramic material according to claim 1, wherein the annealed silicon carbide ring of step (3) is finished by a vertical grinder.
  9. 9. The method for preparing the low-volume resistivity silicon carbide ceramic material according to claim 1, wherein the graphite oxidation furnace treatment process in the step (4) is to heat up at a temperature rising rate of 3-5 ℃ per minute to a temperature keeping time of 15-25h in an oxygen atmosphere at a temperature of 700-850 ℃.
  10. 10. The low volume resistivity silicon carbide ceramic material is characterized in that the silicon carbide ceramic material with the density of less than or equal to 3.21g/cm 3 , the thermal conductivity of more than 200W/(m.k) and the bending strength of more than 400MPa and the volume resistivity of less than 10 2 Ω & cm at room temperature is prepared by the preparation method of any one of claims 1 to 9.

Description

Silicon carbide ceramic material with low volume resistivity and preparation method thereof Technical Field The invention relates to the field of functional ceramics, in particular to a silicon carbide (SiC) ceramic material with low volume resistivity and a preparation method thereof. Background Because of urgent demands of the fields of aviation, aerospace and the like on power consumption, high temperature, speed and extreme environment devices, silicon carbide (SiC) is used as a third-generation compound semiconductor material, and the semiconductor material has the advantages of wide band gap, high breakdown field strength, high thermal conductivity, high saturated electron drift speed, high bonding energy and the like, and is a semiconductor material with great potential in the aspects of solving high speed, high temperature, high power, extreme environment and the like. With the high-speed development of ultra-large scale integrated circuits, the high densification of integrated circuits leads to a drastic increase in the heat productivity of electronic components per unit area, and meanwhile, the electronic components are used in a complex severe reaction environment with high pressure and high temperature for a long time, particularly in etching equipment, materials are required to have high heat conductivity and low volume resistivity. The equipment parts made of silicon carbide (SiC) ceramic materials have the characteristics of high density, high heat conductivity, high bending strength, high elastic modulus and the like, and can adapt to the severe reaction environment with strong corrosiveness and ultrahigh temperature in the manufacturing links of wafer epitaxy, etching and the like, so that the equipment parts are widely applied to main semiconductor equipment such as epitaxial growth equipment, etching equipment, oxidation/diffusion/annealing equipment and the like. The conventional silicon carbide ceramic material is prepared by reaction sintering, so that the problems of low purity, high sintering temperature and the like exist, the CVD-SiC ceramic material has higher uniformity and purity, and the method has stronger process controllability. Meanwhile, the CVD-SiC ceramic material has excellent thermal, electrical and chemical properties, so that the CVD-SiC ceramic material is very suitable for being applied to the semiconductor industry requiring high-performance materials. The conventional method for modifying the SiC ceramic material has doping N, al and other elements as doping elements, and replaces C or Si atoms in a SiC structure by 'racing', so that the carrier concentration and mobility of the silicon carbide semiconductor material are changed. Disclosure of Invention In order to reduce the volume resistivity of the silicon carbide ceramic and enable the silicon carbide ceramic to meet the use requirement of semiconductor etching equipment, the invention provides a preparation method of a silicon carbide (SiC) ceramic material ceramic with low volume resistivity, which is prepared by adopting a CVD method doped with N element. The invention is realized by the following technical scheme that the preparation method of the silicon carbide (SiC) ceramic material ceramic with low volume resistivity comprises the following steps: (1) Placing a graphite substrate in a CVD furnace, vacuumizing the CVD furnace, re-pressing to the atmospheric pressure, introducing process gas, preserving heat for 50-60h to obtain a CVD-SiC ceramic material, cooling to room temperature, and discharging; Preferably, the graphite substrate is selected from annular graphite substrates, a certain number of annular graphite substrates being used as a base of the silicon carbide coating; Preferably, the vacuum degree is controlled below 10 -4 Pa, the holding time is more than or equal to 15min, the temperature is raised to 1500-1650 ℃ at the temperature rising rate of 0.1-3 ℃ per min under the condition of re-pressing to atmospheric pressure, and then the process gas is introduced, wherein the specific re-pressing process is to introduce nitrogen gas, keep positive pressure and raise the temperature, raise the temperature to 900-1100 ℃ at the temperature rising rate of 0.1-3 ℃ per min, keep the temperature for more than or equal to 2 hours, and simultaneously introduce hydrogen gas, and continuously raise the temperature to 1500-1650 ℃ at the temperature rising rate of 0.1-3 ℃ per min. Preferably, the process gas includes a trichlorosilane gas, hydrogen, and nitrogen. More preferably, the purity of the trichlorosilane gas is more than 98 percent, the purity of the hydrogen is more than 99.996 percent, the purity of the nitrogen is more than 99.999 percent, and the higher the purity is, the silicon carbide product is facilitated. Through unique technological parameter regulation, different ratios among the process gases are realized by regulating the flow rate of the plating process gas, thereby realizing resist