Thermal annealing process for producing silicon wafers with improved surface characteristics
US6743495B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2002 |
| Grant date | Jun 1, 2004 |
| Priority date | — |
| Expiry date | May 17, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/21
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A process for manufacturing silicon wafers that reduces the size of silicon wafer surface and/or sub-surface defects without the forming excessive haze. The process entails cleaning the front surface of the silicon wafer at a temperature of at least about 1100° C. by exposing the front surface to a cleaning ambient comprising H2, HF gas, or HCl gas to remove silicon oxide from the front surface and exposing the cleaned front surface of the silicon wafer at a temperature of at least about 1100° C. to a vacuum or an annealing ambient consisting essentially of a mono-atomic noble gas selected from the group consisting of He, Ne, Ar, Kr, and Xe to facilitate the migration of silicon atoms to the exposed agglomerated defects without substantially etching silicon from the front surface of the heated silicon wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.