Device and method for producing single crystal
US5972106A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 1997 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | Feb 10, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1088
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A device and method for producing single crystals by the Czohralski method can control the temperature distribution and thermal history of single crystals to improve the production efficiency and quality of single crystals. The device includes a cylinder coaxially surrounding a single crystal pulling rod, having an upper end airtightly connected to the ceiling of a pulling chamber and a lower end close to the surface of a melt in a crucible. A heat insulating element is attached to the lower end of the cylinder, and is surrounded by a surface of the crystal, the inside wall of the crucible and the surface of the melt. The heat insulating element is sized to occupy 30-95% by volume of the space above the melt, and the space has a height corresponding to the radius of the crystal. The heat insulator has a sufficient heat insulating effect, so that even if the diameter of single crystals is increased, the pulling speed of the crystals does not need to be lowered, the uniformity of temperature of the entire crystal-melt interface is improved, and the ratio of single crystallization is not reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.