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:
Jun. 25, 2002
Filed:
Jun. 23, 2000
Applicant:
Inventors:
Masahiro Shiota, Soraku-gun, JP;
Toshiyuki Shinozaki, Tenri, JP;
Hideyuki Tsuji, Nara, JP;
Toshiaki Kinosada, Osaka-fu, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L 3/10328 ;
U.S. Cl.
CPC ...
H01L 3/10328 ;
Abstract
A heterojunction bipolar transistor having a ballast resistance layer between an AlGaAs emitter layer and an emitter electrode, wherein the ballast resistance layer comprises n-Al Ga As, wherein 0<X<1, and a GaAs selective etching layer is provided between the emitter layer and the ballast resistance layer.