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:
Mar. 15, 2005
Filed:
Jun. 23, 2003
Yasuyoshi Itoh, Tokyo, JP;
Shuuichi Ueno, Tokyo, JP;
Haruo Furuta, Tokyo, JP;
Natsuo Ajika, Tokyo, JP;
Yasuyoshi Itoh, Tokyo, JP;
Shuuichi Ueno, Tokyo, JP;
Haruo Furuta, Tokyo, JP;
Natsuo Ajika, Tokyo, JP;
Renesas Technology Corp., Tokyo, JP;
Abstract
A semiconductor device capable of holding multibit information in one memory cell, and a method of manufacturing the semiconductor device. A trench is formed in a channel portion of an MONOS transistor. Then, a source side portion and a drain side portion in a silicon nitride film of a gate insulating film which interpose the trench are caused to function as first and second electric charge holding portions capable of holding electric charges. In the case in which first electric charges are trapped on the drain side and second electric charges are trapped on the source side, a portion of a gate electrode in the trench functions as a shield. If a fixed potential is given to the gate electrode, the second electric charge holding portion is not influenced by an electric field induced by the first electric charges so that the trapping of the second electric charges is not inhibited.