Method for making a slant-surface silicon wafer having a reconstructed atomic-level stepped surface structure
US5966625A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 1998 |
| Grant date | Oct 12, 1999 |
| Priority date | — |
| Expiry date | Nov 6, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/12
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A single crystal silicon wafer is sliced off so as to have a slant surface that is inclined from plane (001) such that the normal of the slant surface is inclined by 0.01.degree. to 0.2.degree. from direction [001] toward direction [110]. After being cleaned, the silicon wafer is heat-treated at 600-1,300.degree. C. for not less than 1 minute in an ultrapure argon or hydrogen atmosphere containing nitrogen at not more than 0.1 ppm, to thereby cause the slant surface to have a stepped crystal surface structure. The stepped crystal surface structure is constituted of step walls Sa and Sb when it has been formed by a heat treatment in an argon atmosphere, and substantially all of its step walls are of a type Sb when it has been formed by a heat treatment in a hydrogen atmosphere.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.