Patent · US Expired

Method for pulling a single crystal

US6267815A · kind A · utility

2Cited by

3References

7Claims

0Family size

Assignee

Wacker Siltronic Gesellschaft Fur Halbleitermaterialien AG · DE

Inventors

Andreas Ehlert · Mehring, DE
Erich Dornberger · Burghausen, DE
Wilfried Ammon · Burghausen, DE

Key dates

Filing date	Oct 5, 1999
Grant date	Jul 31, 2001
Priority date	—
Expiry date	Oct 5, 2019

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC30B15/203
WIPO fieldSurface technology, coating
WIPO sectorChemistry

Abstract

A method for pulling a single crystal has a monocrystalline seed crystal being brought into contact with molten material and an interface being formed between solid and molten material, and molten material being caused to solidify with the formation of a thin-necked crystal and a cylindrical single crystal. The method is one wherein, during the pulling of the thin-necked crystal, it is ensured that the ratio V/G(r) is above a constant C.sub.crit having the value 1.3*10.sup.-3 cm.sup.2 /Kmin, with V being the pulling rate, with G(r) being the axial temperature gradient at the interface and r being the radial distance from the center of the thin-necked crystal.

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