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:
Mar. 13, 2007
Filed:
Jul. 01, 2003
Akira Usui, Tokyo, JP;
Masatomo Shibata, Ibaraki, JP;
Yuichi Oshima, Ibaraki, JP;
NEC Corporation, Tokyo, JP;
Hitachi Cable, Ltd., Tokyo, JP;
Abstract
The present invention provides a group III nitride semiconductor substrate with low defect density as well as small warp and a process for producing the same; for instance, the process according to the present invention comprises the following series of steps of: forming a metallic Ti filmon a sapphire substrate, followed by treatment of nitration to convert it into a TiN filmhaving fine pores; thereafter growing a HVPE-GaN layerthereon; forming voidsin the HVPE-GaN layerby means of effects of the metallic Ti filmand the TiN film; and peeling the sapphire substratefrom the region of the voidsto remove it therefrom.