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. 20, 1984
Filed:
Jul. 25, 1983
Randall D Isaac, Yorktown Heights, NY (US);
Tak H Ning, Yorktown Heights, NY (US);
Paul M Solomon, Yorktown Heights, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A bipolar transistor device is disclosed having a structure wherein a layer of insulating material extends over and covers the structure substrate up to the region of the extrinsic base around the emitter. A very small area conductive base contact is provided to the extrinsic base, and a protective wall of insulating material is located on the sidewall of the base contact to isolate it from the emitter contact. This structure is made possible by a fabrication process incorporating a double-self-alignment technique wherein the base is self-aligned to a window in the insulating material and the emitter is self-aligned to the base.