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. 14, 1992
Filed:
Jul. 12, 1991
Applicant:
Inventors:
Hisaaki Suga, Saitama, JP;
Yoshinobu Nakada, Tokyo, JP;
Kazuhiro Akiyama, Saitama, JP;
Shunji Ishibashi, Tokyo, JP;
Assignees:
Mitsubishi Materials Corporation, Tokyo, JP;
Nippon Silicon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 11 ; 437 10 ; 437 12 ; 437975 ; 148D / ; 148D / ;
Abstract
A method of gettering unintentional mobile impurities starts with production of an damaged portion on the reverse side of a silicon wafer, and the silicon wafer is placed in a high temperature vacuum ambience so that the unintentional mobile impurities are firstly trapped by the damaged portion and, then, evacuated to the high temperature vacuum ambience.