Method of exhausting silicon oxide
US5573591A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 20, 1995 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Apr 20, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1072
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A monocrystal pulling apparatus according to the Czochralski technique, provided with a flow controller which guides a carrier gas supplied from the top of a pulling cheer to the surface of a melt of a material forming the monocrystal and exhausts the silicon oxide vaporizing from the surface of the melt to the outside of the pulling chamber and which surrounds the pulled monocrystal near the surface of the melt and is provided partially inside a crucible, wherein the flow controller has a tubular portion which has an outer diameter smaller than the inner diameter of the crucible and extends substantially perpendicularly along the direction of downward flow of the carrier gas, a constricted diameter portion which constricts in diameter from the bottom end of the tubular portion and forms a bottom gap with the pulled monocrystal, and an engagement portion which projects out from the top of the tubular portion and forms a top gap at the outer circumference of the tubular portion of the flow controller by supporting the flow controller partially in the pulling chamber. As a result, a first flow path through which the carrier gas flows toward said bottom gap is defined between the insi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.