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. 30, 1993
Filed:
Mar. 26, 1992
Jeffrey L Blouse, Stanfordville, NY (US);
Jack O Chu, Long Island, NY (US);
Brian Cunningham, Highland, NY (US);
Jeffrey P Gambino, Gaylordsville, CT (US);
Louis L Hsu, Fishkill, NY (US);
David E Kotecki, Hopewell Junction, NY (US);
Seshadri Subbanna, Hopewell Junction, NY (US);
Zu-Jean Tien, Saratoga, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of manufacturing a bipolar transistor by use of low temperature emitter process is disclosed. After completion of the usual base and collector formation in a vertical bipolar transistor, an emitter opening is etched in the insulator layer over the base layer at selected locations. A thin layer (less than 500 .ANG.) of in-situ doped amorphous silicon is deposited over the substrate and heated to densify for 30 to 60 minutes at about 650.degree. C. Subsequently an in-situ doped polysilicon layer of 100 to 200 nm is deposited over the amorphous Si film preferably at about 600.degree. C. Subsequently the layers are heated below 600.degree. C. for several hours to convert partially the amorphous Si into a monocrystalline emitter layer over the base regions.