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:
Apr. 12, 2011
Filed:
Oct. 22, 2008
Hiroshi Kujirai, Tokyo, JP;
Hiroshi Kujirai, Tokyo, JP;
Elpida Memory, Inc., Tokyo, JP;
Abstract
A bottom of a gate trench has a first bottom relatively far from an STI and a second bottom relatively near from the STI. A portion, in an active region, configuring the second bottom of the gate trench configures a side-wall channel region, and has a thin-film SOI structure sandwiched between the gate electrode and the STI. On the other hand, a portion configuring the first bottom of the gate trench functions as a sub-channel region. A curvature radius of the second bottom is larger than a curvature radius of the first bottom. In an approximate center in a length direction of the gate trench, a bottom of a trench is approximately flat, and on the other hand, in ends of the length direction, a nearly whole bottom of the trench is curved.