Vitreous silica crucible for pulling of silicon single crystal and method for manufacturing the same
US9758901B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2013 |
| Grant date | Sep 12, 2017 |
| Priority date | — |
| Expiry date | Jun 10, 2033 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P40/57
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention provides a vitreous silica crucible which inhibits a deformation even when used under a high temperature condition for a long time, and a method for manufacturing the same. The vitreous silica crucible comprises: a substantially cylindrical straight body portion having an opening on the top end and extending in a vertical direction, a curved bottom portion, and a corner portion connecting the straight body portion with the bottom portion and a curvature of which is greater than that of the bottom portion, wherein, the vitreous silica crucible comprises a transparent layer on the inside and a bubble layer on the outside thereof, a compressive stress layer in which compressive stress remains in the inner surface side of the transparent layer, and a tensile stress layer in which tensile stress remains and is adjacent to the compressive stress layer at a gradual rate of change of stress.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.