Formation of silicon nitride by nitridation of porous silicon
US5332697A · kind A · utility
Inventors
Key dates
| Filing date | Oct 16, 1991 |
| Grant date | Jul 26, 1994 |
| Priority date | — |
| Expiry date | Oct 16, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/96
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Low residual stress, stoichiometric or near stoichiometric, silicon nitride and silicon carbide films with thicknesses of one micron or greater are produced by reacting porous silicon with a nitrogen or carbon containing gas, such as ammonia or methane, at an appropriate temperature and pressure. The gas diffuses into the pores and reacts with the silicon skeletal structure. Because the initial structure is porous and the pore spaces provide strain relief during the addition reaction and subsequent volume expansion, the resultant film has relatively low residual stress. Either porous or solid films can be produced. This process provides a means to chemically stabilize porous silicon layers and their morphologies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.