Method and apparatus for single crystal silicon production
US5314667A · kind A · utility
Inventors
Key dates
| Filing date | Mar 23, 1992 |
| Grant date | May 24, 1994 |
| Priority date | — |
| Expiry date | Mar 23, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1064
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
There is disclosed a method for growing single crystal material, particularly silicon, in modified Czochralski process furnaces and chambers. The Czochralski process equipment is modified to permit continuous addition of polycrystalline material, preferably in dry powdered form to a molten bath of the material that is maintained at a constant shallow depth. For this purpose, a circular baffle is placed within the crucible containing the molten bath of the material, dividing the crucible into an annular feed zone and a central crystal growth zone. A cylindrical boule is withdrawn from the central crystal growth zone. The surrounding walls of the crucible, and graphite cup that supports the crucible, provide a heating and annealing zone in which the boule is continuously annealed as it is withdrawn from the molten pool. Dopants are also introduced into the annular feed zone, either separately or admixed with the polycrystalline material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.