Silicon wafer, SOI substrate, method for growing silicon single crystal, method for manufacturing silicon wafer, and method for manufacturing SOI substrate
US7704318B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2004 |
| Grant date | Apr 27, 2010 |
| Priority date | — |
| Expiry date | Feb 25, 2024 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B29/06
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
When growing a silicon single crystal free of grown-in defects based on the CZ method, the crystal is pulled out at a critical pulling rate at which a ring-shaped OSF occurrence region vanishes in a center portion of the crystal by using a hot zone structure in which a temperature gradient Gc in a center portion of the crystal is equal to or greater than a temperature gradient Ge in a peripheral portion of the crystal, while supplying an inert gas including hydrogen to an interior of a pulling furnace. The critical pulling rate at which the ring-shaped OSF occurrence region vanishes in the center portion of the crystal is increased, and single crystals free of grown-in defects in which dislocation clusters and COPs can be grown by pulling at a pulling rate higher than that of the prior art.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.