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:
Sep. 12, 1989
Filed:
Oct. 07, 1987
Susumu Kurosawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A new memory device of single transistor type is disclosed. A substrate has a surface portion of low impurity concentration and an inner portion of high impurity concentration, and a trench is formed in the substrate from the surface portion into the inner portion such that the trench surrounds a cell section of the substrate. A switching transistor is formed in the surface portion at the cell section, and a capacitor is formed in the trench such that a MOS type capacitor is constituted by a capacitor electrode, the lower side wall by the inner portion of the substrate and an insulating film therebetween. A bit line is connected to a conductive layer provided at the upper part of the trench, and the conductive layer is connected to the source or drain region of the transistor.