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:
Aug. 14, 2007
Filed:
Jan. 10, 2006
Katsuya Tabuchi, Nagano, JP;
Naoto Fujishima, Nagano, JP;
Mutsumi Kitamura, Nagano, JP;
Akio Sugi, Nagano, JP;
Katsuya Tabuchi, Nagano, JP;
Naoto Fujishima, Nagano, JP;
Mutsumi Kitamura, Nagano, JP;
Akio Sugi, Nagano, JP;
Fuji Electric Co., Ltd., , JP;
Abstract
A semiconductor device is provided that can be manufactured by a simpler process than a conventional lateral trench power MOSFET for use with an 80V breakdown voltage, and which has a lower device pitch and lower on-state resistance per unit area than a conventional lateral power MOSFET for use with a lower breakdown voltage than 80V. A gate oxide film is formed thinly along the lateral surfaces of a trench at a uniform thickness. Then, a gate oxide film is formed along the bottom surface of the trench by selective oxidation so as to be thicker than the gate oxide film on the lateral surfaces of the trench and so as to become progressively thicker from the edge of the bottom surface of the trench toward drain polysilicon.