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:
Jun. 20, 1995
Filed:
Jun. 08, 1994
S Noor Mohammad, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A vertical Triple Heterojunction Bipolar Transistor (THBT) and method of fabrication therefor. The THBT collector has a substrate layer of N.sup.+ silicon, an N.sup.- silicon layer grown on the substrate and a Si/SiGe superlattice grown on the N.sup.- silicon layer. The THBT base is layer of P.sup.+ SiGe grown on the superlattice. The THBT Emitter is a second Si/SiGe Superlattice grown on the base layer. An N.sup.- silicon layer is grown on the emitter superlattice. A layer of N.sup.+ GaP grown on that N.sup.- Si layer. The base is formed, first, by etching a rectangular groove through the emitter, ion implanting dopant into the base layer to form an extrinsic base, etching a V shaped groove into the extrinsic base and, then, filling the grooved base with doped polysilicon.