Patent · US Active

Method for pulling a single crystal composed of silicon from a melt contained in a crucible, and single crystal produced thereby

US9988739B2 · kind B2 · utility

0Cited by

6References

1Claims

0Family size

Assignee

Siltronic AG · DE

Inventors

Erich Gmeilbauer · St. Pantaleon, AT
Robert Vorbuchner · Burghausen, DE
Martin Weber · Borgo San Lazzaro, DE

Key dates

Filing date	Jan 27, 2011
Grant date	Jun 5, 2018
Priority date	—
Expiry date	Sep 18, 2036

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/298
WIPO fieldSurface technology, coating
WIPO sectorChemistry

Abstract

Silicon single crystals are pulled from a melt in a crucible, the single crystal surrounded by a heat shield, the lower end of which is a distance h from the melt surface, wherein gas flows downward between the single crystal and the heat shield, outward between the lower end of the heat shield and the melt, and then upward in the region outside the heat shield. The internal diameter of the heat shield at its lower end is 55 mm or more than the diameter of the single crystal, and the radial width of the heat shield at its lower end is not more than 20% of the diameter of the single crystal. Highly doped single crystals pulled accordingly have a void concentration ≤50 m−3.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.