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:
Nov. 30, 2004
Filed:
Oct. 10, 2003
Susumu Iwamoto, Nagano, JP;
Yasuhiko Onishi, Nagano, JP;
Takahiro Sato, Nagano, JP;
Tatsuji Nagaoka, Nagano, JP;
Abstract
In a trench super junction semiconductor element having a parallel p-n junction layer with n-drift regions and p-partition regions , both extending in a depth direction, being alternately joined, a part in a shape of a three-dimensional curved surface in the end portion of each of trenches is formed in a p-partition region . A section in the p-partition region surrounding the part in a shape of a three-dimensional curved surface of the end portion of each of the trenches is made as a p -region in which an impurity concentration is higher than that in a section thereunder so that an electric field is increased at a boundary between the p -region and the n-drift region , thereby lessening electric field concentration to the part in a shape of a three-dimensional curved surface of the end portion of the trench. Moreover, the section in the p-partition region surrounding the part in a shape of a three-dimensional curved surface in the end portion of the trench can be formed wider than the section thereunder. This inhibits lowering in a breakdown voltage and, along with this, increases reliability of a gate insulator film.