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. 12, 2014
Filed:
Jun. 10, 2013
Shunji Kuragaki, Tokyo, JP;
Shunji Kuragaki, Tokyo, JP;
Sumco Corporation, Tokyo, JP;
Abstract
A method for evaluating metal contamination of a silicon single crystal grown by the Czochralski method using a pulling apparatus in which a voltage can be applied between a crystal suspending member and a crucible comprises the steps of: setting the crystal suspending member as a negative electrode while setting the crucible as a positive electrode in a process for growing a non-convertible portion of the silicon single crystal; applying the voltage; collecting a sample from the non-convertible portion grown in association with the voltage application; and evaluating the metal contamination of the sample by an analysis in which Surface Photo Voltage method is adopted. In a process for growing an end-product convertible portion of the silicon single crystal, the voltage is applied such that the crystal suspending member is set as the positive electrode while the crucible is set as the negative electrode, or the voltage is not applied.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile