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:
Aug. 11, 2009
Filed:
Jul. 27, 2007
Applicants:
Katsuya Ito, Yokkaichi, JP;
Hiroaki Tsunoda, Yokkaichi, JP;
Takanori Matsumoto, Yokkaichi, JP;
Inventors:
Assignee:
Kabushiki Kaisha Toshiba, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/76 (2006.01);
U.S. Cl.
CPC ...
Abstract
A semiconductor device such as a flash memory includes a semiconductor substrate having a surface, and a plurality of trenches formed in the substrate so as to be open at the surface of the substrate, the trenches having opening widths different from each other. The trench with a smaller opening width is formed so as to have a first depth and the trench with a larger opening width has a bottom including opposite ends each of which has a second depth deeper than the first depth and a central portion shallower than the second depth.