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:
Mar. 10, 2015
Filed:
Aug. 14, 2013
Applicant:
Seiko Instruments Inc., Chiba, JP;
Inventor:
Yuichiro Kitajima, Chiba, JP;
Assignee:
Seiko Instruments Inc., Chiba, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 27/088 (2006.01); H01L 21/8234 (2006.01);
U.S. Cl.
CPC ...
H01L 27/088 (2013.01); H01L 21/823462 (2013.01);
Abstract
By covering ends of a field insulating film in a region where a MOS transistor having a relatively thin gate insulating film is formed with a relatively thick gate insulating film, a channel region of the MOS transistor having the relatively thin gate insulating film is set apart from an inversion-preventing diffusion layer formed under the field insulating film so as not to be influenced by film thickness fluctuation of the field insulating film, etching fluctuation of the relatively thick gate insulating film, and impurity concentration fluctuation at both sides of the channel due to the inversion-preventing diffusion layer.