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:
Oct. 03, 1989
Filed:
Oct. 29, 1987
Reinhard Glang, Reston, VA (US);
San-Mei Ku, Poughkeepsie, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A semiconductor process for fabricating bipolar devices of one type and extendible to include bipolar devices of a second type in the same epi-layer. The process protects selected surfaces of the epi-layer against deleterious processes associated with the formation of future emitter/contact regions for the devices. Subsequently, such emitter/contact regions are formed beneath such protected surfaces and contribute to enhanced device performance. The process also provides improved planarization of an insulating layer on the epi-layer by chemical-mechanical polishing. The planarization in conjunction with a mask formed in the insulating layer facilitates the formation of self-aligned emitter/base regions to appropriate thicknesses for high performance devices.