Precision controlled precipitation of oxygen in silicon
US5593494A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 14, 1995 |
| Grant date | Jan 14, 1997 |
| Priority date | — |
| Expiry date | Mar 14, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3225
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Process for controlling the density of oxygen precipitate nucleation centers in single crystal silicon. In the process, the single crystal silicon is annealed at a temperature of at least about 350.degree. C. to cause the formation of oxygen precipitate nucleation centers in the single crystal silicon. During the annealing step, the single crystal silicon is heated (or cooled) to achieve a first temperature, T.sub.1, which is between about 350.degree. C. and about 500.degree. C. The temperature is then increased from T.sub.1 to a second temperature, T.sub.2, which is between about 500.degree. C. and about 750.degree. C. with the average rate of temperature increase from T.sub.1 to T.sub.2 being less than about 25.degree. C. per minute. The annealing is terminated at a point in time when the oxygen precipitate nucleation centers are capable of being dissolved by heat-treating the silicon at a temperature not in excess of about 1150.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.