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:
Apr. 13, 2010
Filed:
Oct. 24, 2007
Applicants:
Masahito Kodama, Aichi-ken, JP;
Eiko Hayashi, Aichi-ken, JP;
Masahiro Sugimoto, Aichi-ken, JP;
Inventors:
Assignees:
Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi-gun, Aichi-ken, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, Aichi-ken, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/20 (2006.01); H01L 21/36 (2006.01);
U.S. Cl.
CPC ...
Abstract
The invention provides a method for producing a group III nitride based semiconductor having a reduced number of crystal defects. A GaN layeris epitaxially grown on a sapphire substratehaving C-plane as a main plane (FIG.A). Then, the layer is wet-etched by use of a 25% aqueous TMAH solution at 85° C. for one hour, to thereby form an etch pit(FIG.B). Then, a GaN layeris grown on the GaN layerthrough the ELO method (FIG.C). The thus-formed GaN layerhas a screw dislocation density lower than that of the GaN layer