Apparatus for chemical vapor deposition using an axially symmetric gas flow
US4798165A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 25, 1988 |
| Grant date | Jan 17, 1989 |
| Priority date | — |
| Expiry date | Jan 25, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B25/14
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
In a chemical vapor deposition chamber, an improved technique for providing deposition materials to the growth surface is described. The gas carrying deposition materials is constrained to have axial symmetry thereby providing a uniform deposition of materials on the substrate. The gas can be initially directed toward the substrate with a generally uniform perpendicular velocity. The gas can be introduced into the deposition chamber through a multiplicity of apertures and is extracted from the vicinity of the substrate in a manner to preserve the axial symmetry. The apparatus permits convenient control of the deposition process by varying the distance between apparatus introducing the gas carrying the deposition materials and the substrate. The flow of gas minimizes the problems arising from autodoping of the growth layer of material. The flow of gas and generally small size of the deposition chamber minimize particulate contamination of the growing film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.