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:
Feb. 28, 1989
Filed:
Aug. 06, 1987
Grigory Kogan, Portland, OR (US);
National Semiconductor Corp., Santa Clara, CA (US);
Abstract
The present invention provides a vertical punch-through cell comprising a silicon substrate, an epitaxial silicon layer overlying the substrate, an N+ buried column line formed at the interface between the substrate and the epitaxial layer, an N+ diffusion region formed above and spaced apart from the buried column line at the surface of the epitaxial layer, a field oxide layer formed over the epitaxial layer and having an contact opening formed therein over the N+ diffusion region, a polysilicon layer formed on the surface of the field oxide layer to extend through the contact opening to make contact with the N diffusion region, a layer of dielectric material formed over the polysilicon layer, and a layer of conductive material formed over the dielectric material.