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:
May. 31, 2022
Filed:
Nov. 04, 2019
Hitachi, Ltd., Tokyo, JP;
Masahiro Masunaga, Tokyo, JP;
Shintaroh Sato, Tokyo, JP;
Akio Shima, Tokyo, JP;
Ryo Kuwana, Tokyo, JP;
Isao Hara, Tokyo, JP;
HITACHI, LTD., Tokyo, JP;
Abstract
An n type semiconductor layer is formed over an n type semiconductor substrate made of silicon carbide, a p type impurity region is formed in the semiconductor layer, and an n type drain region and an n type source region are formed in the impurity region. A field insulating film having an opening that selectively opens a part of the impurity region located between the drain and source regions is formed over the impurity region and the drain and source regions. A gate insulating film is formed over the impurity region in the opening, and a gate electrode is formed on the gate insulating film. Here, a field relaxation layer having an impurity concentration higher than that of the impurity region is formed in at least a part of the impurity region located between the drain and source regions in plan view and located below the field insulating film.