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:
May. 20, 1997
Filed:
Jun. 02, 1995
Applicant:
Inventors:
Dwight C Streit, Seal Beach, CA (US);
Aaron K Oki, Torrance, CA (US);
Liem T Tran, Torrance, CA (US);
Assignee:
TRW Inc., Redondo Beach, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
257197 ; 257198 ;
Abstract
An InAlAs/InGaAlAs heterojunction bipolar transistor that includes a constant quaternary InGaAlAs collector layer. Graded InGaAlAs collector layers are provided on each side of the quaternary collector layer to minimize transitions through the constant collector layer. The InAlAs/InGaAlAs HBT may also include one or more of a graded InGaAlAs emitter-base transition region, a graded-doping InGaAs base layer, and a graded-composition InGaAlAs base layer.