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:
Nov. 25, 2014
Filed:
Jul. 13, 2011
Applicant:
Masatoshi Koyama, Kanagawa, JP;
Inventor:
Masatoshi Koyama, Kanagawa, JP;
Assignee:
Sumitomo Electric Device Innovations, Inc., Yokohama-shi, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 21/02 (2006.01); H01L 29/45 (2006.01); H01L 29/66 (2006.01); H01L 21/306 (2006.01); H01L 29/20 (2006.01);
U.S. Cl.
CPC ...
H01L 21/30621 (2013.01); H01L 29/2003 (2013.01); H01L 29/452 (2013.01); H01L 29/66462 (2013.01);
Abstract
A method for fabricating a semiconductor device includes forming a recess to an AlGaN layer by etching, the AlGaN layer having an Al composition ratio of 0.2 or greater, the recess having a bottom having an RMS roughness less than 0.3 nm, forming a first Ta layer having a thickness of 4 nm to 8 nm on the bottom of the recess, and annealing the first Ta layer to make an ohmic contact in the AlGaN layer.