Highly polishable, highly thermally conductive silicon carbide, method of preparation and applications thereof.

摘要

Silicon carbide is produced by chemical vapor deposition at temperatures from 1340-1380 DEG C, deposition chamber pressures of 180-200 torr, H2/methyltrichlorosilane ratio of 4-10 and deposition rate of 1-2 mu m/min. Furthermore, H2 supplied as a part of the gas stream contains less than about 1 part per million (ppm) O2gas, and various means are provided to exclude particulate material from the deposition chamber. The silicon carbide is polishable to <5 ANGSTROM RMS as measured on a Talystep mechanical profiler and has a thermal conductivity of at least about 300 W/mk. The silicon carbide is particularly suitable for applications where high polishability and thermal conductivity is desired, such as hard disc drives and read/write heads of head disc assemblies, and also optical apparatus which require a very high polish.