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:
Aug. 29, 1995
Filed:
Aug. 09, 1994
Timothy S Henderson, Richardson, TX (US);
Darrell G Hill, Plano, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
The invention described herein includes, in one of its forms, a method for fabricating a bipolar transistor having a reduced base-collector capacitance. A specific embodiment includes forming a selectively etchable material 44 over a highly doped subcollector layer 42, removing portions of the selectively etchable material 44 and then growing collector 46, base 48, and emitter 50 layers over the structure. The selectively etchable material 44 may then be removed to form an undercut region between the highly doped subcollector layer 42 and the highly doped base 48. The structure provides the advantage of improved high-frequency and high-power operation.