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:
Sep. 24, 2013
Filed:
Sep. 01, 2011
Hideto Sugawara, Fukuoka-ken, JP;
Hideto Sugawara, Fukuoka-ken, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
According to one embodiment, a nitride semiconductor stacked structure having a first surface includes a substrate, a first buffer layer, a first crystal layer, a second buffer layer and a second crystal layer. A step portion is provided in the substrate and includes an upper surface, a lower surface, and a side surface between the upper surface and the lower surface. The first buffer layer includes InAlGaN (0≦s≦0.05, 0≦t≦1) and covers the lower surface and the side surface. The first crystal layer is provided on the first buffer layer, includes InAlGaN (0≦s≦0.05, 0≦t≦0.05), and has an upper surface provided above the upper surface of the substrate. The second buffer layer includes InAlGaN (0≦s≦0.05, 0≦t≦1) and continuously covers the upper surface of the first crystal layer and the upper surface of the substrate. The second crystal layer covers the second buffer layer, includes InAlGaN (0≦s≦0.05, 0≦t≦0.05), and has the first surface.