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:
Sep. 09, 1997
Filed:
Jun. 06, 1995
Madjid Hafizi, Santa Monica, CA (US);
William E Stanchina, Thousand Oaks, CA (US);
Hughes Electronics, Los Angeles, CA (US);
Abstract
A submicron emitter heterojunction bipolar transistor and a method for fabricating the same is disclosed. The fabrication process includes lattice matched growth of subcollector, collector, base, emitter, and emitter cap layers in sequential order on a semi-insulating semiconductor substrate. An emitter cap mesa, an emitter/base/collector mesa and a subcollector mesa are formed. Dielectric platforms are formed extending the base/collector layers laterally. Sidewalls are formed on the sides of emitter cap mesa and the sides of the extended base/collector layers and undercuts are etched into the emitter layer and the upper portion of the subcollector layer. This forms an overhang on the emitter cap mesa with respect to the emitter layer and an overhang on the base/collector layers with respect to the upper portion of the subcollector layer. Emitter, base and collector contacts are simultaneously formed, the base contact aligned to the edge of the emitter cap overhang and the collector contact aligned to the edge of the base/collector layer overhang.