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. 15, 1985
Filed:
Dec. 27, 1983
David L Bergeron, Winooski, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An improved device isolated by a trench formed in an N conductivity type semiconductor substrate is provided which has first and second spaced apart P conductivity type regions butted to a sidewall of the trench. An N+ doped region is disposed adjacent to the sidewall of the trench extending from the surface of the semiconductor substrate to an N+ buried region and interposed between the first and second P type conductivity regions. The dopant concentration in the N+ doped region is higher than that of the semiconductor substrate but not higher than the dopant concentration of the N+ buried region. More particularly, a lateral PNP transistor, isolated within a trench formed in an N type conductivity semiconductor substrate having an N+ buried region, has emitter and collector regions butted against a sidewall of the trench, along with the transistor's base region. A highly doped N+ base segment is disposed within the base region of the transistor adjacent to the sidewall of the trench extending from the surface of the substrate to the N+ buried region, and interposed between the emitter and collector regions.