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. 29, 1991
Filed:
Jun. 06, 1990
Wilhelmus J Josquin, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
The collector region (20) of a bipolar transistor (T) and a first well region (3) for an insulated gate field effect transistor (IGFET) (P) are formed of one conductivity type at respective first and second device areas (10 and 12) of a semiconductor body (1a). After definition of an insulated gate (9), opposite conductivity type impurities are introduced to form source and drain regions (90 and 91) of the IGFET (P) and at the same time to dope a dopable layer (30) on the first device area (10) to form an opposite conductivity type doped layer (30) for forming an extrinsic base region (40). An insulating layer (50, 51) is then provided to cover the first and second device areas (10 and 12). Impurities for forming an intrinsic base region (41) and emitter region (80) of the bipolar transistor (T) are introduced through an opening (60, 61) in the insulating layer (50, 51) which also serves to mask the IGFET (P) from these impurities.