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:
Dec. 28, 1993
Filed:
Oct. 17, 1991
Applicant:
Inventor:
Takayuki Matsukawa, Hyogo, JP;
Assignee:
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ; H01L / ; G11C / ;
U.S. Cl.
CPC ...
365149 ; 365185 ; 257 68 ; 257 71 ;
Abstract
A MOS type semiconductor memory device and a method of controlling the same device that can improve the lifetime (reliability) of a capacitor dielectric film is disclosed. In accordance with the MOS type semiconductor memory device, the cell plate (upper electrode 9) voltage V.sub.GG of the capacitor is set to be greater than zero and less than an arithmetic average of the maximum logic voltage V.sub.H and the minimum logic voltage V.sub.L applied to the storage node. The lifetime of the capacitor dielectric film is improved in comparison with a cell plate voltage of V.sub.H /2 when an ON (Oxidized Nitride) film is used as a capacitor dielectric film.