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:
Oct. 07, 2014
Filed:
Sep. 20, 2012
Ngk Insulators, Ltd., Nagoya, JP;
Makoto Miyoshi, Inazawa, JP;
Mikiya Ichimura, Ichinomiya, JP;
Tomohiko Sugiyama, Nagoya, JP;
Mitsuhiro Tanaka, Tsukuba, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
Provided is an epitaxial substrate for a semiconductor device, which has excellent schottky contact characteristics that are stable over time. The epitaxial substrate for a semiconductor device includes a base substrate, a channel layer formed of a first group III nitride containing at least Ga and having a composition of InAlGaN (x1+y1+z1=1), and a barrier layer formed of a second group III nitride containing at least In and Al and having a composition of InAlGaN (x2+y2+z2=1), wherein the barrier layer has tensile strains in an in-plane direction, and pits are formed on a surface of the barrier layer at a surface density of 5×10/cmor more and 1×10/cmor less.