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. 07, 2006
Filed:
Jun. 28, 2002
Kazufumi Suenaga, Yokohama, JP;
Kiyoshi Ogata, Yokohama, JP;
Kazuhiko Horikoshi, Kawasaki, JP;
Jun Tanaka, Chigasaki, JP;
Hisayuki Kato, Kokubunji, JP;
Keiichi Yoshizumi, Kokubunji, JP;
Hisahiko Abe, Mito, JP;
Kazufumi Suenaga, Yokohama, JP;
Kiyoshi Ogata, Yokohama, JP;
Kazuhiko Horikoshi, Kawasaki, JP;
Jun Tanaka, Chigasaki, JP;
Hisayuki Kato, Kokubunji, JP;
Keiichi Yoshizumi, Kokubunji, JP;
Hisahiko Abe, Mito, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
The present invention is a high quality semiconductor memory device using a ferroelectric thin film capacitor as a memory capacitor at a high manufacturing yield, the ferroelectric thin film of the capacitor is specified such that the relative standard deviation of crystal grain sizes is 13% or less, to thereby ensure a high remanent polarization value and a small film fatigue (large rewritable number).