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. 27, 2011
Filed:
Jan. 31, 2007
Masahiko Urano, Fukushima, JP;
Izumi Fusegawa, Fukushima, JP;
Masahiko Urano, Fukushima, JP;
Izumi Fusegawa, Fukushima, JP;
Shin-Etsu Handotai Co., Ltd., Tokyo, JP;
Abstract
The present invention is a method for determining a relative distance between a reference member placed above a melt surface and the melt surface upon pulling a silicon single crystal out of a raw material melt in a crucible by a CZ method characterized by at least: pulling the silicon single crystal applying a magnetic field; taking a picture of a real image of the reference member and a mirror image of the reference member reflected on the melt surface with a detector; processing the picture taken of the real image and the mirror image of the reference member as different pictures by separating the picture taken; and calculating the relative distance between the real image and the mirror image of the reference member from the processed pictures to determine the relative distance between the reference member and the melt surface.