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. 17, 1998
Filed:
Oct. 02, 1996
Eiji Sakagami, Yokohama, JP;
Kiyomi Naruke, Ebina, JP;
Kabushiki Kaisha Toshiba, , JP;
Abstract
The present invention discloses a nonvolatile semiconductor memory device having a memory cell transistor in which an offset region is provided as a charge carrier injecting region. An insulating film and a gate electrode is formed in order of mention on a semiconductor substrate. Source/drain regions are formed on the surface of the semiconductor substrate with the gate electrode interposed therebetween. The drain has an LDD (Lightly Doped Drain) structure. Furthermore, a layered film of silicon oxide films and a SiN film is provided on a channel region between an edge of the gate electrode and a source diffusion layer. To be more specific, the layered film is formed in such a way that the SiN film is interposed between the silicon oxide films, constituting a side wall of the gate electrode. The SiN film is a charge carrier accumulating layer. Contact holes are formed in an insulating film between layers, respectively reaching the source and drain regions. Each of the contact holes are filled with a conductive material (contact plug). A conductive barrier film (diffusion protecting film) is provided on the bottom and to the inner wall portions of the contact hole. The contact plugs respectively connect the source and the drain to upper layer, aluminium wiring.