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:
Aug. 05, 2014
Filed:
Mar. 21, 2011
Tetsuya Kai, Yokohama, JP;
Yoshio Ozawa, Yokohama, JP;
Ryota Fujitsuka, Yokkaichi, JP;
Yoshitaka Tsunashima, Yokohama, JP;
Tetsuya Kai, Yokohama, JP;
Yoshio Ozawa, Yokohama, JP;
Ryota Fujitsuka, Yokkaichi, JP;
Yoshitaka Tsunashima, Yokohama, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
According to one embodiment, a semiconductor memory device with memory cells each composed of a vertical transistor, comprises a silicon layer formed into a columnar shape on a silicon substrate, a gate insulating film part in which a tunnel insulating film, a charge storage layer, and a block insulating film are formed to surround the sidewall surface of the silicon layer, and a stacked structure part formed to surround the sidewall surface of the gate insulating film part and in which a plurality of interlayer insulating films and a plurality of control gate electrode layers are stacked alternately. The silicon layer, gate insulating film part, and control gate electrode layer constitute the vertical transistor. The charge storage layer has a region lower in trap level than a region facing the control gate electrode layer between the vertical transistors.