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. 11, 1994
Filed:
Nov. 27, 1991
Brian McFarlane, Campbell, CA (US);
Frank Marazita, San Jose, CA (US);
John E Readdie, San Jose, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A lateral pnp transistor for use in programmable logic arrays. The lateral pnp has a layer of oxide disposed between a polysilicon layer and the base along the base width. The oxide layer prevents diffusion of the N+ dopant contained in the polysilicon layer into the N- base region. The base region thus remains N- and the resulting transistor has improved breakdown voltage characteristics while retaining the speed advantages of polysilicon contact layers. The lateral pnp transistor is manufactured by a method which requires minimal deviation from other methods used to manufacture lateral pnp transistors.