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:
Apr. 02, 2002
Filed:
Jul. 30, 1999
Applicant:
Inventors:
Assignee:
DaimlerChrysler AG, Stuttgart, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 2/1331 ;
U.S. Cl.
CPC ...
H01L 2/1331 ;
Abstract
A method for producing a heterobipolar transistor, arranged on a substrate of semiconductor material on which is grown a semiconductor sequence for a collector, a base and an emitter, which method includes: etching the layer sequence to form a transistor with a mesa structure, carrying out a first planarizing step to the upper limit of the base during which the surface of the base is protected by a protecting portion of the emitter layer adjacent to the base; removing this protective layer; depositing a metal contact layer for the base; carrying out a second planarizing step for the base emitter mesa; and finally depositing a connecting metallization layer for the collector, base and emitter.