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:
Sep. 13, 2005
Filed:
Apr. 14, 2003
Applicants:
Eiji Kamiya, Kamakura, JP;
Kazuhiro Shimizu, Yokohama, JP;
Inventors:
Eiji Kamiya, Kamakura, JP;
Kazuhiro Shimizu, Yokohama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01L021/8238 ; H01L021/336 ;
U.S. Cl.
CPC ...
Abstract
In a memory cell, a gate oxide film is formed on a surface of semiconductor substrate and a first floating gate is formed on the gate oxide film. An insulating film is formed on a first floating gate and a second floating gate is formed on the insulating film. The first and second floating gates constitute a floating gate in the memory cell. An insulating film between the first floating gate and the second floating gate acts as an etching stopper when a polysilicon constituting the second floating gate is etched.