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:
Dec. 11, 2007
Filed:
Aug. 29, 2005
Yoshihiro Yamaguchi, Fukuoka, JP;
Kenji Oota, Tokyo, JP;
Yoshihiro Yamaguchi, Fukuoka, JP;
Kenji Oota, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A P-type first diffusion layer is formed by diffusing P-type impurities on a front side of an N-type semiconductor substrate, and an N-type fourth diffusion layer which is shallower than the first diffusion layer is formed by diffusing N-type impurities on the front side, and a P-type second diffusion layer is locally formed in a ring-shape so as to be exposed on the lateral side by diffusing P-type impurities on the back side, and P-type impurities are diffused on the back side of the substrate and a P-type third diffusion layer is locally formed so as to be distributed inward from the second diffusion layer and not to be exposed to the lateral side, and the P-type second diffusion layer and the P-type third diffusion layer are formed in the two-stage structure, thereby various characteristics can be improved.