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. 31, 2007
Filed:
Apr. 01, 2002
Applicant:
Eisuke Suekawa, Tokyo, JP;
Inventor:
Eisuke Suekawa, Tokyo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 29/74 (2006.01); H01L 31/111 (2006.01);
U.S. Cl.
CPC ...
Abstract
An IGBT includes a plurality of ndoped regions () selectively formed in a main surface () of a psemiconductor layer () opposite from an n type semiconductor layer () without being connected to the n type semiconductor layer (). The ndoped regions () are formed in corresponding relation to and only under channel regions (CH-CH) of structures (-), respectively. This lowers the effective concentration of the psemiconductor layer () on the ndoped regions () to reduce the number of holes injected from a collector layer () in an off state, reducing a leakage current.