Kinetic Investigation On The Deposition Of Sic From Methyltrichlorosilane And Hydrogen

Kinetics of chemical vapor deposition of SIC from MTS/H-2 was investigated by magnetic suspension balance in a wide range of processing conditions. The results show that the deposition rate exhibits three deposition behaviours depending on temperature: at lower temperatures (T<1000 degrees C), the deposition rate increases slowly with increasing temperature. The apparent active energy is from 130 to 222kJ/mol; at mediate temperatures (from 1000 to 1100 degrees C), the deposition rate increases drastically and the apparent active energy is from 100 to 130kJ/mol. However, at higher temperatures (T>1300 degrees C), it decreases quickly. The deposition rate First rises with both of pressure and flow rate and then almost keeps constant. The transformation point lies in 200sccm and from 2 to 3kPa, respectively. Residence time is seen to have a strong positive effect on the deposition rate. Longer residence time corresponding to temperature changing from 1000 degrees C to 900 degrees C causes a decrease by 24 times in the deposition rate.