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:
Mar. 20, 2018
Filed:
Jul. 08, 2016
Renesas Electronics Corporation, Tokyo, JP;
Koichi Arai, Ibaraki, JP;
Kenichi Hisada, Ibaraki, JP;
RENESAS ELECTRONICS CORPORATION, Tokyo, JP;
Abstract
In a silicon carbide semiconductor device having a trench type MOS gate structure, the present invention makes it possible to inhibit the operating characteristic from varying. A p-type channel layer having an impurity concentration distribution homogeneous in the depth direction at the sidewall part of a trench is formed by applying angled ion implantation of p-type impurities to a ptype body layer formed by implanting ions having implantation energies different from each other two or more times after the trench is formed. Further, although the p-type impurities are introduced also into an n-type drift layer at the bottom part of the trench when the p-type channel layer is formed by the angled ion implantation, a channel length is stipulated by forming an n-type layer having an impurity concentration higher than those of the p-type channel layer, the p-type body layer, and the n-type drift layer between the p-type body layer and the n-type drift layer. By those measures, it is possible to inhibit the operating characteristic from varying.