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. 25, 2007
Filed:
Jan. 30, 2006
Yukio Hayakawa, Aizuwakamatsu, JP;
Hiroyuki Nansei, Aizuwakamatsu, JP;
Yukio Hayakawa, Aizuwakamatsu, JP;
Hiroyuki Nansei, Aizuwakamatsu, JP;
Spansion LLC, Sunnyvale, CA (US);
Abstract
A single cell that has a gate insulating film formed with an ONO film is provided in a region in which two bit lines cross one word line. The single cell is a four-bit multi-value cell, and has four charge accumulation regions. Two plug-like control electrodes are provided in the region surrounded by the word line and the bit lines. A bias is applied to one of the plug-like control electrodes and the word line so that the portion on the surface of the semiconductor substrate that is located immediately below the word line and corresponds to the location of the bias-applied control electrode is put into an accumulation state or a depletion state. In this manner, the width of the channel is adjusted, and the charge holding state of each of the four charge accumulation regions is controlled through the channel width adjustment.