Silicon single crystal wafer and method for producing it
US6190452A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 1999 |
| Grant date | Feb 20, 2001 |
| Priority date | — |
| Expiry date | Jun 8, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S117/917
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
There is disclosed a method for producing a silicon single crystal in accordance with the Czochralski method wherein a crystal is pulled with controlling a temperature in a furnace so that .DELTA.G may be 0 or a negative value, where .DELTA.G is a difference between the temperature gradient Gc (.degree. C./mm) at the center of a crystal and the temperature gradient Ge (.degree. C./mm) at the circumferential portion of the crystal, namely .DELTA.G=(Ge-Gc), wherein G is a temperature gradient in the vicinity of a solid-liquid interface of a crystal from the melting point of silicon to 1400.degree. C., and with controlling a pulling rate in a range between a pulling rate corresponding to a minimum value of the inner line of OSF region and a pulling rate corresponding to a minimum value of the outer line, when OSF region is generated in an inverted M belt shape in a defect distribution chart which shows a defect distribution in which the horizontal axis represents a diameter of the crystal and the vertical axis represent a pulling rate. There can be provided a method of producing a silicon single crystal wafer by CZ method wherein OSF in the ring shape distribution generated when being…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.