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:
Feb. 24, 1998
Filed:
Aug. 23, 1995
Applicant:
Inventors:
John Kevin Twynam, Tanri, JP;
Motoji Yagura, Tanri, JP;
Toshiyuki Shinozaki, Tanri, JP;
Toshiaki Kinosada, Izumi, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
257197 ; 257198 ;
Abstract
A heterojunction type AlGaAs/GaAs bipolar transistor includes an n-GaAs collector layer, a p.sup.+ -GaAs base layer and an n-Al.sub.x Ga.sub.1-x As emitter layer formed in a stack, and an n-Al.sub.y Ga.sub.1-y As ballast resistance layer formed on the emitter layer. The ballast resistance layer has an Al concentration y in the range of 0<y<0.4, and a resistance higher than that of the emitter layer.