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:
Jan. 26, 1988
Filed:
Apr. 18, 1986
Timothy M Lindenfelser, Eagan, MN (US);
David A Hanson, Apple Valley, MN (US);
Sperry Corporation, New York, NY (US);
Abstract
A method for fabricating high performance bipolar transistors using a single polycrystalline silicon layer whereby horizontally and vertically scaled base/emitter junctions are achieved. In an extrinsic base transistor, a composite sandwich of overlying layers of poly silicon, oxide and nitride are deposited over a substrate containing field oxide isolated monocrystalline transistor sites having buried subcollectors and sinker regions. The composite sandwich is thereafter selectively oxidized to define base, emitter and collector regions with the relative thickness of the composite sandwich and the grown oxide being controlled to assure proper horizontal extrinsic base to emitter spacings and shallow vertical intrinsic base to emitter junctions, upon completing subsequent implant and annealing steps. Each active transistor site is also surrounded by a ring-like, channel stopper which is physically isolated from the channel stopper of each other device.