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:
Oct. 15, 2013
Filed:
Dec. 20, 2011
Applicant:
Hiroaki Takasu, Chiba, JP;
Inventor:
Hiroaki Takasu, Chiba, JP;
Assignee:
Seiko Instruments Inc., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 29/788 (2006.01);
U.S. Cl.
CPC ...
Abstract
Provided is an electrically erasable and programmable nonvolatile semiconductor memory device having a small hole in a second conductivity-type drain region, a tunnel insulating film formed on the surface of the hole, and a protrusion extended from the floating gate electrode and arranged to fill the hole. Further a tunneling restriction region which is an electrically floating first conductivity type region arranged in a vicinity of the surface of the drain region around the hole to define the size of the tunnel region through which the tunnel current flows.