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:
Jul. 28, 2015
Filed:
Aug. 09, 2012
Makoto Miyoshi, Inazawa, JP;
Shigeaki Sumiya, Handa, JP;
Mikiya Ichimura, Ichinomiya, JP;
Tomohiko Sugiyama, Nagoya, JP;
Mitsuhiro Tanaka, Tsukuba, JP;
Makoto Miyoshi, Inazawa, JP;
Shigeaki Sumiya, Handa, JP;
Mikiya Ichimura, Ichinomiya, JP;
Tomohiko Sugiyama, Nagoya, JP;
Mitsuhiro Tanaka, Tsukuba, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
Provided is a crack-free epitaxial substrate with reduced warping, in which a silicon substrate is used as a base substrate. The epitaxial substrate includes a (111) single crystal Si substrate, a superlattice layer group in which a plurality of superlattice layers are laminated, and a crystal layer. The superlattice layer is formed of a first unit layer and a second unit layer made of group-III nitrides having different compositions being alternately and repeatedly laminated. The crystal layer is made of a group-III nitride and formed above the base substrate so as to be positioned at an upper side of the superlattice layer group relative to the base substrate. The superlattice layer group has a compressive strain contained therein. In the superlattice layer group, the more distant the superlattice layer is from the base substrate, the greater the compressive strain becomes.