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. 16, 1998
Filed:
Feb. 22, 1996
Applicant:
Inventor:
Masafumi Shimizu, Nara-ken, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; H01L / ; H01L / ;
U.S. Cl.
CPC ...
257197 ; 257 76 ; 257191 ; 257196 ; 257615 ; 257623 ;
Abstract
A hetero-junction bipolar transistor comprising a collector layer, a base layer and an emitter layer formed stepwise in this order wherein the emitter layer comprises a plurality of layers including an AlGaAs layer, and a passivation layer is formed at a stepwise portion between the base layer and the emitter layer, and of a material having a bandgap larger than that of the base layer, and provided with a phosphide layer on the surface thereof.