Process for the production of ultra high purity polycrystalline silicon
US4826668A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1987 |
| Grant date | May 2, 1989 |
| Priority date | — |
| Expiry date | Jun 11, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B33/035
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention is directed to an improved process for producing ultra high purity polycrystalline silicon which process provides for increased production capacity and electrical power efficiency. The process comprises recycling the exhaust gases of the silane pyrolysis reactor after the gases have been preferably first cooled and filtered utilizing a pocket-type reaction zone enclosure having a particular effective radius thereby effectively decreasing the amount of silicon powder formation. Preferably, the rate of recycle flow is sufficient to entrain silicon powder in the reactor and remove the powder from the reactor with the exiting exhaust gases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.