Si/SiC composite material and method for making Si/SiC composite material
US5494439A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1994 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | Mar 24, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B35/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A silicon/silicon carbide material which eliminates contamination by outgassing and direct contact is described as well as wafer processing pans made of this material and wafer processing methods using the silicon/silicon carbide material. An ultraclean silicon/silicon carbide material may be formed by first forming a Si/SiC part by prior art methods. The Si/SiC part then is subjected to a temperature sufficient to cause the impurities within the silicon carbide to either react and/or diffuse into the silicon fill. The contaminated silicon fill is then removed, either by high temperature evaporation or by a chemical etch. Clean silicon is then impregnated within the pore space of the silicon carbide pan. The part which results has ultraclean silicon and silicon carbide grains which have most, if not all, of the impurities removed from the surface of the grains. Thus, an ultraclean material results which will not outgas or directly contaminate silicon wafers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.