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:
Apr. 07, 1998
Filed:
Mar. 25, 1996
Hiroki Shirai, Tokyo, JP;
NEC Corporation, , JP;
Abstract
A non-volatile semiconductor memory cell comprises a source region having an N.sup.+ type diffusion layer, an N.sup.- diffusion layer, and N type diffusion layer, the N.sup.- type diffusion layer being formed by injecting phosphorus ions by an inclined rotating ion injecting method. The overlap width of the N.sup.- type diffusion layer and the floating gate electrode is larger than the overlap width of the N.sup.+ type diffusion layer and the floating gate electrode, and the junction depth of the N type diffusion layer is larger than the junction depth of the N.sup.+ type diffusion layer. Thus, in flash memory having memory cells according to the present invention, even if the size of the memory cells is reduced, erase time can be shortened without sacrificing erase function and performance.