Photo-CVD system
US5215588A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 17, 1992 |
| Grant date | Jun 1, 1993 |
| Priority date | — |
| Expiry date | Jan 17, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/488
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A photo-assisted chemical vapor deposition system includes a reaction chamber, a susceptor in the reaction chamber supporting a wafer, a source for introducing reactant gas into the reaction chamber through an inlet port, and a cover positioned in sealed relationship to the housing and partially bounding the reaction chamber, the cover including a plurality of elongated light pipe openings each having a length comparable to the thickness of a boundary layer of the reactant gas and a diameter-to-length ratio small enough to maintain one-dimensional purge gas flow through the light pipe openings. A plurality of transparent windows are disposed in sealed relationship with the cover and bound an outer end of each of the light pipe openings. Ultraviolet light is introduced through the light pipe openings, which also provide a thick gas layer through which reactant species of the reactant gas must diffuse to reach the window surface. Inert purging gas having a velocity large enough to reduce the concentration of the reactant gas is introduced into the light pipe openings and flows out of the open ends thereof, impeding diffusion of reactant gas molecules toward the windows. Clouding of t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.