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:
Jan. 01, 2013
Filed:
Dec. 17, 2008
Ryo Sakamoto, Akita, JP;
JO Shimizu, Akita, JP;
Tsuneo Ito, Akita, JP;
Takashi Egawa, Nagoya, JP;
Dowa Electronics Materials Co., Ltd., Tokyo, JP;
National University Corporation Nagoya Institute of Technology, Nagayo, JP;
Abstract
A semiconductor material is provided comprising: a composition graded layer, formed on a Si substrate or an interlayer formed thereon, comprising a composition of AlGaN graded such that a content ratio of Al in the composition decreases continuously or discontinuously in a crystal growing direction; a superlattice composite layer, formed on the composition graded layer, comprising a high Al-containing layer comprising a composition of AlGaN and a low Al-containing layer comprising a composition of AlGaN that are laminated alternately; and a nitride semiconductor layer formed on the superlattice composite layer.