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:
Jul. 16, 2002
Filed:
Mar. 17, 2000
Masao Nakajima, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The present invention is a ferroelectric memory chip having a memory cell region in which there is provided a plurality of memory cells, each having a ferroelectric capacitor, this ferroelectric memory chip being characterized in that there is formed an electromagnetic wave shield layer, which shields the above-mentioned memory cell region against electromagnetic waves from the outside. The electromagnetic wave shield layer is constituted, for example, from either a conductive layer, or a semiconductor layer, which is provided above and/or below the memory cell region, and preferably is connected so as to constitute the same electric potential. Providing such an electromagnetic wave shield layer eliminates the direct irradiation of electromagnetic waves on a word line, plate line and bit line inside the memory cell region, thus making it possible to prevent a change in a storage state by an unexpected electric field being applied to a ferroelectric capacitor inside a memory cell.