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:
Mar. 16, 2004
Filed:
Jun. 21, 2002
Kazuhito Matsukawa, Tokyo, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
A method of regenerating a semiconductor wafer which allows a used wafer, even if the wafer contains a crystal defect such as a COP, to be regenerated into a high-quality semiconductor wafer is provided. A used silicon wafer is polished in a step S Next, the used silicon wafer is immersed in mixed acids including at least two kinds of acids in a step S A surface treatment is performed on the used silicon wafer to planarize the surface of the used silicon wafer in a step S Then, a high temperature annealing process is performed in a step S to ultimately obtain a regenerate wafer. The high temperature annealing process includes either a first high temperature annealing process which is performed at a high temperature of 1200° C. or higher in an argon atmosphere for 30 to 60 minutes, or a second high temperature annealing process which is performed at a high temperature of 1200° C. or higher in a hydrogen atmosphere for 30 to 60 minutes.