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:
May. 01, 2012
Filed:
Jul. 14, 2009
Applicants:
Miwako Akiyama, Tokyo, JP;
Yusuke Kawaguchi, Kanagawa-ken, JP;
Yoshihiro Yamaguchi, Saitama-ken, JP;
Inventors:
Miwako Akiyama, Tokyo, JP;
Yusuke Kawaguchi, Kanagawa-ken, JP;
Yoshihiro Yamaguchi, Saitama-ken, JP;
Assignee:
Kabushiki Kaisha Toshiba, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 29/76 (2006.01); H01L 31/062 (2012.01);
U.S. Cl.
CPC ...
Abstract
An impurity concentration profile in a vertical direction of a p type base contact layer of a power semiconductor device has a two-stage configuration. In other word, the impurity concentration profile is highest at an upper face of the p type base contact layer, has a local minimum value at a position other than the upper face and a lower face of the base contact layer, and has a local maximum value at a position lower than the position of the local minimum value.