The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 12, 1995
Filed:
May. 01, 1995
Michael A Pickering, Dracut, MA (US);
Jitendra S Goela, Andover, MA (US);
Lee E Burns, Woburn, MA (US);
CVD, Incorporated, Woburn, MA (US);
Abstract
Silicon carbide is produced by chemical vapor deposition at temperatures from 1340.degree.-1380.degree. C., deposition chamber pressures of 180-200 torr, H.sub.2 /methyltrichlorosilane ratio of 4-10 and deposition rate of 1-2 .mu.m/min. Furthermore, H.sub.2 supplied as a part of the gas stream contains less than about 1 part per million (ppm) O.sub.2 gas, and various means are provided to exclude particulate material from the deposition chamber. The silicon carbide is polishable to <5 .ANG. 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.