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:
Nov. 12, 1991
Filed:
Jun. 29, 1989
Applicant:
Inventor:
Wolfgang M Feist, Burlington, MA (US);
Assignee:
Raytheon Company, Lexington, MA (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437 31 ; 437200 ; 437984 ; 437 57 ; 148D / ; 148D / ;
Abstract
A method of forming a bipolar transistor. A base region is implanted into an epitaxial layer. An emitter and collector contact regions are formed of doped polysilicon on the epitaxial layer, the emitter being formed over the base region. The implant is below the surface of the epitaxial layer in all regions not covered by the collector region. Low resistance silicide contacts, such as titanium or cobalt, are formed on the structure in a self-aligned fashion. This method is well suited for forming BJTs as part of BiCMOS circuits.