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:
Jul. 08, 2014
Filed:
Oct. 23, 2009
Shigeru Umeno, Tokyo, JP;
Keiichiro Hiraki, Tokyo, JP;
Hiroaki Taguchi, Tokyo, JP;
Sumco Corporation, Tokyo, JP;
Abstract
By determining a control direction of a pulling-up velocity without using a position or a width of an OSF region as an index, a subsequent pulling-up velocity profile is fed back and adjusted. A silicon single crystal ingot that does not include a COP and a dislocation cluster is grown by a CZ method, a silicon wafer is sliced from the silicon single crystal ingot, reactive ion etching is performed on the silicon wafer in an as-grown state, and a grown-in defect including silicon oxide is exposed as a protrusion on an etching surface. A growing condition in subsequent growing is fed back and adjusted on the basis of an exposed protrusion generation region. As a result, feedback with respect to a nearest batch can be performed without performing heat treatment to expose a defect.