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:
Apr. 23, 2019
Filed:
Oct. 31, 2012
Sumco Corporation, Minato-ku, Tokyo, JP;
Toshiaki Sudo, Akita, JP;
Tadahiro Sato, Akita, JP;
Eriko Kitahara, Akita, JP;
Takeshi Fujita, Akita, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
Buckling of a vitreous silica crucible or fall of a sidewall into the crucible is effectively suppressed. Furthermore, dislocations in a silicon single crystal are suppressed to enhance the yield of the single crystal. The vitreous silica crucible is used to pull single-crystal silicon and includes the cylindrical sidewall having an upward-opening rim, a mortar-shaped bottom including a curve, and a round portion connecting the sidewall and the bottom. The round portion is provided in such a manner that the curvature of the inner surface thereof is gradually increased from the sidewall toward the bottom in a section passing through the rotation axis of the vitreous silica crucible.