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:
Aug. 14, 2001
Filed:
Sep. 14, 1999
Yasuhiro Kogure, Hyogo, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
A silicon single crystal producing apparatus and method are disclosed. Contamination of a hot molten liquid due to a chuck mechanism is prevented where an upper end part of the silicon single crystal is gripped by the chuck mechanism and is raised after the silicon single crystal is produced. Elevation and rotation of the chuck mechanism can be controlled independently of elevation and rotation of a pulling wire. Before the upper end part of the silicon single crystal is gripped at a bottom part of a pull chamber, the chuck mechanism is set at a standby position at a top of the pull chamber. The chuck mechanism is lowered from the standby position to the grip position. A rotation frequency of the chuck mechanism during lowering is selected as a rotation frequency free of resonance. After lowering and gripping of the silicon single crystal, the chuck mechanism is raised while being rotated in synchronism with the pulling wire.