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. 12, 2015
Filed:
Mar. 05, 2014
Sumitomo Electric Industries, Ltd., Osaka-shi, Osaka, JP;
Ken Nakata, Yokohama, JP;
Keiichi Yui, Yokohama, JP;
Tsuyoshi Kouchi, Yokohama, JP;
Isao Makabe, Yokohama, JP;
Hiroyuki Ichikawa, Yokohama, JP;
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
The semiconductor device includes a SiC substrate; an aluminum nitride layer provided on the substrate and having an island-shaped pattern consisting of plural islands: a channel layer provided on the AlN layer and comprising a nitride semiconductor; an electron supplying layer provided on the channel layer and having a band gap larger than that of the channel layer; and a gate, source and drain electrodes on the electron supply layer. The AlN layer has an area-averaged circularity Y/X of greater than 0.2. Y is a sum of values obtained by multiplying circularities of the plural islands by areas of the plural islands respectively, X is a sum of the areas of the plural islands. The circularity are calculated by a formula of (4π×area)/(length of periphery)where the area and the length of periphery are an area and a length of periphery of each island.