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:
Dec. 08, 2009
Filed:
Jul. 14, 2006
Toshiaki Ono, Tokyo, JP;
Wataru Sugimura, Tokyo, JP;
Takayuki Kubo, Tokyo, JP;
Akira Higuchi, Tokyo, JP;
Ken Nakajima, Tokyo, JP;
Toshiaki Ono, Tokyo, JP;
Wataru Sugimura, Tokyo, JP;
Takayuki Kubo, Tokyo, JP;
Akira Higuchi, Tokyo, JP;
Ken Nakajima, Tokyo, JP;
Sumco Corporation, Tokyo, JP;
Abstract
A process for producing a silicon single crystal includes the steps of bringing a seed crystal into contact with a silicon melt, gradually pulling the seed crystal from the melt so as to form a neck having a tapered portion and a constant diameter portion, then pulling a silicon single crystal. The atmosphere used during neck formation is a hydrogen-containing atmosphere prepared by adding a hydrogen-containing substance to an inert gas. The hydrogen-containing substance has a hydrogen gas equivalent concentration in the hydrogen-containing atmosphere of 3 to 20%.