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:
Jul. 20, 1993
Filed:
Feb. 19, 1991
Kuniyoshi Yoshikawa, Tokyo, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A nonvolatile semiconductor device according to the present invention comprises a memory cell array having memory cells arranged in a matrix, each emory cell being composed of a floating gate electrode, control gate electrode, a source diffusion layer, and drain diffusion layer, tunnel oxide films formed on the side walls of the floating gate electrodes on the side where adjacent memory cells, sharing the control gate electrode, face each other, and an erasure gate electrode formed so as to sandwich the tunnel oxide films between the floating gate electrodes and itself, and electrically connected to the source diffusion layer at nearly an equal distance from the adjacent memory cells sharing the control gate electrode.