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. 07, 1995
Filed:
Jan. 21, 1993
Applicant:
Inventor:
Tetsuro Nozu, Tokyo, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kanagawa, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ;
U.S. Cl.
CPC ...
257197 ; 257198 ; 257618 ; 257622 ;
Abstract
The present invention is directed toward a heterojunction bipolar transistor integrated circuit in which the collector layers of two heterojunction bipolar transistors are provided on a semi-insulating substrate. The collector layers have at least one surface that is sloped relative to the substrate. Base layers are provided on the sloped portions a common emitter layer is provided in contact with the base layers. Alternatively, the common emitter layer is provided on the substrate and etched to form to sloped surface thereon. Base and collector layers are then formed on the sloped surfaces of the common emitter layer.