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:
Sep. 12, 2017
Filed:
May. 31, 2013
Vitreous silica crucible for pulling of silicon single crystal and method for manufacturing the same
Sumco Corporation, Minato-ku, Tokyo, JP;
Toshiaki Sudo, Akita, JP;
Ken Kitahara, Akita, JP;
Akihiro Aiba, Akita, JP;
Kazushi Ousyuya, Akita, JP;
Fumie Yoshida, Akita, JP;
Makiko Hinooka, Akita, JP;
Eriko Kitahara, Akita, JP;
Tadahiro Sato, Akita, JP;
SUMCO CORPORATION, Tokyo, JP;
Abstract
The present invention provides a vitreous silica crucible which inhibits a deformation even when used under a high temperature condition for a long time, and a method for manufacturing the same. The vitreous silica crucible comprises: a substantially cylindrical straight body portion having an opening on the top end and extending in a vertical direction, a curved bottom portion, and a corner portion connecting the straight body portion with the bottom portion and a curvature of which is greater than that of the bottom portion, wherein, the vitreous silica crucible comprises a transparent layer on the inside and a bubble layer on the outside thereof, a compressive stress layer in which compressive stress remains in the inner surface side of the transparent layer, and a tensile stress layer in which tensile stress remains and is adjacent to the compressive stress layer at a gradual rate of change of stress.