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:
Dec. 27, 1988
Filed:
Sep. 09, 1987
Hideo Kato, Kawasaki, JP;
Hiroshi Iwahashi, Yokohama, JP;
Masamichi Asano, Tokyo, JP;
Akira Narita, Kawasaki, JP;
Shinichi Kikuchi, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In an electrically-erasable/programmable nonvolatile semiconductor memory device according to the invention, a one-bit memory cell is constituted by a series circuit of a selecting MOS transistor and a data storage MOS transistor. A floating gate electrode and a control gate electrode are formed in the data storage MOS transistor, One portion of the floating gate electrode is formed on a channel region of the data storage MOS transistor through a gate insulating film. The other portion of the floating gate electrode is formed on a drain region of the data storage MOS transistor through a gate insulating film, a portion of which is sufficiently thinner than the gate insulating film. One and the other portions of the floating gate electrode are structurally separated from each other but are electrically connected with each other on a field region. A control gate electrode having substantially the same shape as that of the floating gate electrode is formed thereon through a gate insulating film.