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:
May. 30, 2017
Filed:
Sep. 04, 2014
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Kazuhito Nishitani, Chigasaki, JP;
Katsuhiro Sato, Yokohama, JP;
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Abstract
According to one embodiment, a nonvolatile semiconductor memory device is provided. The element isolation insulating bodies form active areas extending in one direction along a surface of a semiconductor substrate in a surface region of the semiconductor substrate, and partition the surface region into the active areas. The tunnel insulating films are formed on the active areas respectively. The floating gate electrodes are formed on the tunnel insulating films respectively. The inter-gate insulating films are formed on the floating gate electrodes. The control gate electrodes are provided on the inter-gate insulating films. The source regions and drain regions are formed in the active areas respectively. Each of the active areas has steps at side surfaces. A width of a portion of each of the active areas deeper than the steps is larger than that of a portion of each of the active areas shallower than the steps.