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:
Jun. 08, 2004
Filed:
May. 30, 2003
Hitoshi Kitagawa, Miyagi-ken, JP;
Makoto Sasaki, Miyagi-ken, JP;
ALPS Electric Co., Ltd, Tokyo, JP;
Abstract
A thin-film capacitor device for performing temperature compensation is manufactured by layering a first dielectric thin-film and a second dielectric thin-film, wherein the second dielectric thin-film has a thickness t , wherein t ={&egr; &tgr; /(C/S)}·{1/(&tgr;/&kgr;)}, wherein C/S represents a sheet capacitance, &egr; represents the dielectric constant of vacuum, &tgr; represents a desired temperature coefficient of capacitance, &tgr; represents the temperature coefficient of capacitance of the second dielectric thin-film, and &kgr; represents the relative dielectric constant of the second dielectric thin-film, a target value of a grain size of the second dielectric thin-film is determined by selecting the grain size satisfying the formula (&tgr;/&kgr;)/(&tgr; /&kgr; )>1, wherein &tgr; represents the temperature coefficient of capacitance of the principal crystal grain, and &kgr; represents relative dielectric constant of the principal crystal grain, and the second dielectric thin-film is deposited so that the grain size becomes the target value.