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:
Jun. 08, 2010
Filed:
Jun. 12, 2008
Kazuyoshi Shiba, Tokyo, JP;
Hideyuki Yashima, Tokyo, JP;
Kazuyoshi Shiba, Tokyo, JP;
Hideyuki Yashima, Tokyo, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
In a memory cell array on a main surface of a semiconductor substrate, a floating gate electrode for accumulating charges for information is arranged. The floating gate electrode is covered with a cap insulating film and a pattern of a first insulating film formed thereon. Further, over the entire main surface of the semiconductor substrate, a second insulating film is deposited so that it covers the pattern of the first insulating film and a gate electrode. The second insulating film is formed by a silicon nitride film formed by a plasma CVD method. The first insulating film is formed by a silicon nitride film formed by a low-pressure CVD method. By the provision of such a first insulating film, it is possible to suppress or prevent water or hydrogen ions from diffusing to the floating gate electrode, and therefore, the data retention characteristics of a flash memory can be improved.