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:
Nov. 24, 2009
Filed:
Apr. 21, 2005
Takaaki Aoki, Okazaki, JP;
Mikimasa Suzuki, Toyohashi, JP;
Yukio Tsuzuki, Nukata-gun, JP;
Tomofusa Shiga, Nukata-gun, JP;
Takaaki Aoki, Okazaki, JP;
Mikimasa Suzuki, Toyohashi, JP;
Yukio Tsuzuki, Nukata-gun, JP;
Tomofusa Shiga, Nukata-gun, JP;
DENSO CORPORATION, Kariya, JP;
Abstract
On the surface of a silicon nitride film, there is formed a thermal oxide film, over which a CVD oxide film is then formed to provide a silicon oxide film of two-layered structure films. Moreover, the total thickness of the two-layered structure films is set to a value from 5 nm to 30 nm. Thus, the silicon oxide film is made into the two-layered structure films of the thermal oxide film and the CVD oxide film to thereby achieve the thickness of the silicon oxide film. As a result, it is possible to prevent a Vth from being lowered by a charge trap phenomenon and to prevent the Vth from fluctuating due to the enlargement of the bird's beak length by the silicon oxide film.