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:
Nov. 27, 2007
Filed:
May. 18, 2005
Norihito Fukatsu, Yonezawa, JP;
Kazuyuki Egashira, Saga, JP;
Senrin Fu, Saitama, JP;
Sumco Corporation, Tokyo, JP;
Abstract
The invention provides an apparatus for producing a single crystal, and a method for producing a silicon single crystal using the same. An apparatus for producing a single crystal includes a heating device which heats polycrystalline silicon raw material held in a crucible to form silicon melt, and a pulling up device which grows a silicon single crystal while pulling it up from the silicon melt accompanied with rotation. By providing the apparatus with a magnetic field generation unit which applies to the silicon melt a cusp magnetic field a shape of neutral plane of which is symmetric around the rotation axis of the silicon single crystal and is curved in the upward direction, various conditions for producing a silicon single crystal having a defect free region is relaxed, and a silicon single crystal having a defect free region is produced at high efficiency.