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CN-122013160-A - Surface treatment process method for preparing silicon carbide material by CVD method

CN122013160ACN 122013160 ACN122013160 ACN 122013160ACN-122013160-A

Abstract

The invention relates to a surface treatment process method for preparing a silicon carbide material by a CVD method, which comprises the following steps of placing the silicon carbide material prepared by the CVD method in an oxidation furnace for oxidation treatment to form an oxide layer on the surface of the silicon carbide material; and removing the oxide layer. The oxidation treatment comprises the steps of introducing oxygen, heating from room temperature to a first preset temperature at a speed of 3-5 ℃ per minute, carrying out heat preservation treatment, continuously heating to a second preset temperature at a speed of 2-3 ℃ per minute, heating to a target process temperature at a speed of 0.8-1.2 ℃ per minute, carrying out heat preservation oxidation, cooling to the first preset temperature at a speed of 2.5-3.5 ℃ per minute, cooling to a third preset temperature at a speed of 1.3-1.8 ℃ per minute, and naturally cooling. The silicon carbide material is treated through an oxidation process, the defect layer is uniformly oxidized, an oxide layer (silicon dioxide film) is formed on the surface of the defect layer, and then the oxide layer is removed, so that the surface defect is eliminated, and further the service life of the SiC material and the stability and yield of an etching process are obviously improved.

Inventors

  • LI XIANGXIANG
  • CHEN HUI
  • HE SHAOLONG
  • HU RENHAO
  • Ding Liuning

Assignees

  • 浙江六方半导体科技有限公司

Dates

Publication Date
20260512
Application Date
20251219

Claims (10)

  1. 1. The surface treatment process method for preparing the silicon carbide material by the CVD method is characterized by comprising the following steps of: Placing the silicon carbide material prepared by the CVD method into an oxidation furnace, and performing oxidation treatment to form an oxide layer on the surface of the silicon carbide material; And removing the oxide layer.
  2. 2. The surface treatment process according to claim 1, wherein the oxidation treatment comprises the steps of: Introducing oxygen, heating from room temperature to a first preset temperature at a speed of 3-5 ℃ per minute, and performing heat preservation treatment; continuously heating to a second preset temperature at a speed of 2-3 ℃ per minute, heating to a target process temperature at a speed of 0.8-1.2 ℃ per minute, and performing thermal insulation oxidation; Cooling to the first preset temperature at the speed of 2.5-3.5 ℃ per minute, cooling to the third preset temperature at the speed of 1.3-1.8 ℃ per minute, and naturally cooling.
  3. 3. The surface treatment process according to claim 2, wherein the flow rate of oxygen is 16-24l/min.
  4. 4. A surface treatment process according to claim 2 or 3, wherein 8 oxygen nozzles are uniformly distributed in the oxidation furnace, and the flow rate of each oxygen nozzle is 2-3l/min.
  5. 5. The surface treatment process according to claim 2, wherein the first preset temperature is 750-850 ℃ and the time of the heat preservation treatment is 1-2 hours.
  6. 6. The surface treatment process according to claim 2, wherein the second preset temperature is 1200-1300 ℃.
  7. 7. The surface treatment process according to claim 2, wherein the target process temperature is 1350-1450 and the oxidation process time is 25-35 hours.
  8. 8. The surface treatment process according to claim 2, wherein the third preset temperature is 550-650 ℃.
  9. 9. The surface treatment process according to claim 1, wherein the oxide layer has a thickness of 1 μm and is removed by chemical cleaning.
  10. 10. The surface treatment process according to claim 1, wherein after the temperature is raised to a second preset temperature, stopping introducing oxygen, introducing nitrogen with a flow of 16-24l/min, preserving heat for 60-120min, stopping introducing nitrogen, continuing introducing oxygen, and raising the temperature to a target process.

Description

Surface treatment process method for preparing silicon carbide material by CVD method Technical Field The invention relates to the field of silicon carbide materials, in particular to a surface treatment process method for preparing a silicon carbide material by a CVD method. Background In the process of integrated circuit etching technology, the etching ring and the spray header are continuously impacted and corroded by etching ions in the reaction cavity, so that the etching ring and the spray header are key consumable materials in equipment, and the product stability and the yield of the etching technology are directly determined. The silicon carbide material has the characteristics of high heat conductivity, high compactness and high purity, has better corrosion resistance and stability than the silicon material, and prolongs the service life by about 3 times than the silicon material, so that the silicon carbide material is preferentially used for preparing etching rings and spray header parts in the prior process. The silicon carbide prepared by the CVD method has high hardness and is very fragile, so that the difficulty is very high after machining, machining defects (mainly including chipping, microcracks and the like) exist on the machined surface, and the defects are more easily etched to cause particle pollutants at the defect positions due to large stress during etching, so that wafers are scrapped, and the yield is lost. Therefore, how to treat the surface defects of the silicon carbide material becomes a key point for improving the service life and stability of the etching ring and the spray head of the silicon carbide material. Disclosure of Invention The invention provides a surface treatment process method for preparing a silicon carbide material by a CVD method, which aims to remove defects and improve the service life of a part during etching. In order to achieve the above purpose, the invention adopts the following technical scheme: A surface treatment process method for preparing silicon carbide material by a CVD method comprises the following steps: Placing the silicon carbide material prepared by the CVD method into an oxidation furnace, and performing oxidation treatment to form an oxide layer on the surface of the silicon carbide material; And removing the oxide layer. Preferably, the oxidation treatment comprises the steps of: Introducing oxygen, heating from room temperature to a first preset temperature at a speed of 3-5 ℃ per minute, and performing heat preservation treatment; continuously heating to a second preset temperature at a speed of 2-3 ℃ per minute, heating to a target process temperature at a speed of 0.8-1.2 ℃ per minute, and performing thermal insulation oxidation; Cooling to the first preset temperature at the speed of 2.5-3.5 ℃ per minute, cooling to the third preset temperature at the speed of 1.3-1.8 ℃ per minute, and naturally cooling. Preferably, the flow rate of oxygen is 16-24l/min. Preferably, 8 paths of oxygen gas nozzles are uniformly distributed in the oxidation furnace, and the flow rate of each path of oxygen gas nozzle is 2-3l/min. Preferably, the first preset temperature is 750-850 ℃, and the heat preservation treatment time is 1-2h. Preferably, the second preset temperature is 1200-1300 ℃. Preferably, the target process temperature is 1350-1450, and the oxidation process time is 25-35h. Preferably, the third preset temperature is 550-650 ℃. Preferably, the oxide layer has a thickness of 1 μm and is removed by chemical cleaning. Preferably, after the temperature is raised to the second preset temperature, stopping introducing oxygen, introducing nitrogen with the flow of 16-24l/min, preserving the temperature for 60-120min, then stopping introducing nitrogen, continuing introducing oxygen, and raising the temperature to the target process. The defects at the silicon carbide grain boundary are more, the diffusion is fast, the oxidation rate is fast, the defects along the grain boundary recess are easy to form, nitrogen atoms can be preferentially diffused to the grain boundary by introducing nitrogen before oxidation, siCN is formed, and the rapid diffusion of oxygen along the grain boundary in the subsequent oxidation process is obviously inhibited. Preferably, in the oxidation treatment process, a multi-point thermocouple is used for monitoring the temperature in the oxidation furnace, and the temperature uniformity is controlled at +/-5 ℃. The oxidation of silicon carbide is extremely sensitive to temperature, and small differences in temperature can directly lead to differences in oxidation rate, so that oxidation depths of different areas are obviously different, and an 'oxidation corrosion pit' is formed, so that the temperature uniformity is required to be controlled to be +/-5 ℃. Compared with the prior art, the invention has the beneficial effects that: The silicon carbide material is treated through an oxidation process, the defect layer is