Comprehensive process for low temperature epitaxial growth
US5378651A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 1993 |
| Grant date | Jan 3, 1995 |
| Priority date | — |
| Expiry date | Apr 30, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02636
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A system and method for growing low defect density epitaxial layers of Si on imperfectly cleaned Si surfaces by either selective or blanket deposition at low temperatures using the APCVD process wherein a first thin, e.g., 10 nm, layer of Si is grown on the surface from silane or disilane, followed by the growing of the remainder of the film from dichlorosilane (DCS) at the same low temperature, e.g., 550.degree. C. to 850.degree. C. The subsequent growth of the second layer with DCS over the first layer, especially if carried out immediately in the very same deposition system, will not introduce additional defects and may be coupled with high and controlled n-type doping which is not available in a silane-based system. Further, in order to achieve an optimal trade-off between the need for an inert ambience to promote silane reaction at low temperature and the need for a hydrogen ambience to prevent surface oxidation from inadvertant residual impurities, depositions are carried out in an ambience composed primarily of He but always containing some H.sub.2. Also, the relative deposition rates on a patterned surface of polycrystalline Si on insulator areas and single crystal Si on si…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.