Method for elimination of contaminants prior to epitaxy
US6514886B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 2000 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Sep 22, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/906
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
According to the disclosed method, the surface of a semiconductor wafer is covered by a protective oxide. For example, the protective oxide can be silicon oxide and the semiconductor wafer can be a silicon wafer. The semiconductor wafer is then placed in a CVD reactor at a first temperature. For example, the first temperature can be approximately 650° C. Contaminants and the protective oxide are then removed from the surface of the semiconductor wafer at the first temperature. For example, contaminants and the protective oxide can be removed from the surface of a silicon wafer by using an etchant, such as Hydrogen Chloride (HCl), and a precursor, such as Dichlorosilane (SiH2Cl2 or “DCS”), in appropriate proportions. While contaminants and the protective oxide are being removed by the action of HCl and DCS, any silicon being removed from the surface of the silicon wafer, is being replenished so that there is no net change in the amount of silicon on the surface of the wafer. After removal of the contaminants and the protective oxide, epitaxial growth is performed on the surface of the semiconductor wafer at the first temperature. For example, silicon germanium epitax…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.