The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 20, 2006
Filed:
Apr. 09, 2004
Hideki Watanabe, Tokyo, JP;
Isamu Miyamoto, Tokyo, JP;
Toshiyuki Fujiwara, Tokyo, JP;
Sumitomo Mitsubishi Silicon Corporation, Tokyo, JP;
Abstract
The present invention teaches an apparatus for pulling a single crystal, whereby a radial temperature gradient of a seed crystal and/or a neck is reduced to a minimum so as to inhibit occurrence of thermal stress and prevent induction of dislocations, thereby resulting in an improvement in dislocation-free rate of single crystals to be pulled in cases where a single crystal is pulled with a seed crystal and/or a neck being heated using an auxiliary heating device. The apparatus comprises a crucible to be charged with a melt, a heater located around the crucible, and an auxiliary heating device including a heating section which can be located so as to surround a seed crystal in a position near and above the melt, a transfer mechanism for withdrawing the heating section from a passing area of a single crystal, and a covering section to cover a clearance between the heating section and the seed crystal extending from the heating section.