Apparatus and method for the uniform distribution of crystal defects upon a silicon single crystal
US5704973A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1996 |
| Grant date | Jan 6, 1998 |
| Priority date | — |
| Expiry date | Jun 18, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1032
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Proposed is an improvement in the method and single crystal growing chamber for the preparation of a single crystal rod of silicon by the Czochralski method, according to which the distance between the surface of the melt of silicon contained in a crucible and the lower surface of the top wall of the crystal growing chamber is equal to or larger than the diameter of the crucible and the heat-insulating cylinder surrounding the crucible containing the melt of silicon and the heater has such a height as to reach the lower surface of the top wall of the chamber so as to keep the single crystal rod under growing is kept at a temperature not lower than 700.degree. C. until reaching the lower surface of the top wall of the chamber thereby decreasing the density of the crystal defects of BMD type in the seed end of the single crystal rod as grown so that the uniformity in the distribution of BMD density is increased throughout the single crystal rod.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.