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:
Nov. 02, 2010
Filed:
Mar. 18, 2008
Tatsuo Shimizu, Tokyo, JP;
Koichi Muraoka, Sagamihara, JP;
Masato Koyama, Miura-gun, JP;
Shoko Kikuchi, Kawasaki, JP;
Tatsuo Shimizu, Tokyo, JP;
Koichi Muraoka, Sagamihara, JP;
Masato Koyama, Miura-gun, JP;
Shoko Kikuchi, Kawasaki, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
A nonvolatile semiconductor memory includes a source area and a drain area provided on a semiconductor substrate with a gap which serves as a channel area, a first insulating layer, a charge accumulating layer, a second insulating layer (block layer) and a control electrode, formed successively on the channel area, and the second insulating layer is formed by adding an appropriate amount of high valence substance into base material composed of substance having a sufficiently higher dielectric constant than the first insulating layer so as to accumulate a large amount of negative charges in the block layer by localized state capable of trapping electrons, so that the high dielectric constant of the block layer and the high electronic barrier are achieved at the same time.