Method and apparatus for manufacturing a silicon single crystal having few crystal defects, and a silicon single crystal and silicon wafers manufactured by the same
US5968264A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1998 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | Jul 2, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1088
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
In method for manufacturing a silicon single crystal in accordance with a Czochralski method, during the growth of the silicon single crystal, pulling is performed such that a solid-liquid interface in the crystal, excluding a peripheral 5 mm-width portion, exists within a range of an average vertical position of the solid-liquid interface .+-.5 mm. There is also disclosed a method for manufacturing a silicon single crystal in accordance with the Czochralski method, wherein during the growth of a silicon single crystal, a furnace temperature is controlled such that a temperature gradient difference .DELTA.G (=Ge-Gc) is not greater than 5.degree. C./cm, where Ge is a temperature gradient (.degree.C./cm) at a peripheral portion of the crystal, and Gc is a temperature gradient (.degree.C./cm) at a central portion of the crystal, both in an in-crystal descending temperature zone between 1420.degree. C. and 1350.degree. C. or between a melting point of silicon and 1400.degree. C. in the vicinity of the solid-liquid interface of the crystal. The method maintains high productivity and enables a silicon single crystal and silicon wafers to be manufactured such that a defect density is very…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.