Silicon carbide with low nitrogen content and method for preparation
US8858709B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 2007 |
| Grant date | Oct 14, 2014 |
| Priority date | — |
| Expiry date | Apr 21, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B29/36
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A physical vapor deposition method of growing a crystal includes providing a seed crystal and a source material in spaced relation inside of a growth crucible that is at least in-part gas permeable to an unwanted gas. The growth chamber is heated whereupon the source material sublimates and is transported via a temperature gradient in the growth chamber to the seed crystal where the sublimated source material precipitates. Concurrent with heating the growth chamber, a purging gas is caused to flow inside or outside of the growth crucible in a manner whereupon the unwanted gas flows from the inside to the outside of the growth crucible via the gas permeable part thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.