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.

Date of Patent:
Feb. 24, 1998

Filed:

Nov. 21, 1996
Applicant:
Inventor:

Yuukoh Katoh, Tokyo, JP;

Assignee:

NEC Corporation, Tokyo, JP;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11C / ;
U.S. Cl.
CPC ...
365145 ; 257295 ; 257296 ;
Abstract

A semiconductor memory device is composed of a plurality of memory cells. Each memory cell is comprised of a field effect transistor formed on a semiconductor substrate, wherein said field effect transistor is composed of a gate electrode structure which is composed of a gate insulating film and a gate electrode provided thereon, and source and drain regions. The memory cell is further composed of a ferroelectric capacitor composed of a lower electrode connected to said gate electrode, an upper electrode, and a capacitive ferroelectric film disposed between said upper and lower electrodes. In this case, an area of said ferroelectric capacitor is smaller than an area of one of said gate electrode and an active region of said gate electrode such that an electric field applied to said ferroelectric film is larger than a coercive electric field of said ferroelectric film and an electric field applied to said gate insulating film is smaller than a breakdown electric field of said gate insulating film.


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