【摘要】 采用 MTS( CH3 Si Cl3 )为原料 ,H2 为载气 ,Ar为稀释气 ,在 1 0 0 0～ 1 2 0 0℃范围以内以石墨为基体 ,通过化学气相沉积法 ( CVD)制备了 Si C块体材料。在特定的工艺条件下 ,Si C的生长速率可达 0 .6mm/h。结合实验结果 ,研究了常压 Si C- CVD过程中 ,对 Si C生长速率产生影响的若干因素的作用 ,初步探索了基体尺寸与沉积室尺寸的比例、沉积温度、稀释气流量以及沉积时间对沉积速率的影响 ,综合分析了提高 Si C生长速率的原因更多还原

【Abstract】 Good SiC can be synthesized by chemical vapor deposition (CVD) but its deposition rate is very low. We succeeded in raising the average deposition rate in preparing SiC coating to as high as 0.6 mm/h under the best conditions we could devise. We used CVD to deposit polycrystalline β silicon carbide coating onto graphite substrate at a temperature range of 1000~1200℃, using MTS (CH 3SiCl 3) as precursor and H 2 or Ar as dilution gas. The thickness of SiC coatings we prepared was 2~3 mm. Fig. 3 shows that when Ar flow rate was 250 mL/min and deposition time was 2.5 h, the average deposition rate increases with increasing temperature, the highest being 0.6 mm/h at 1200°C. When temperature was 1200℃ and deposition time was 2.5 h, the average deposition rate increases with increasing flow rate of argon gas until it peaks at 0.6 mm/h at a flow rate of 250 mL/min. When temperature was 1200℃ and Ar flow rate was 250 mL/min, the average deposition rate increases with increasing deposition time until it peaks at 0.6 mm/h at a deposition time of 2.5 h. In section 2 we give effective reasons for the phenomena in Figs.3, 4, and 5.更多还原