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, 2009
Filed:
Jan. 19, 2007
Takehisa Sasabayashi, Ritto, JP;
Masayuki Ishihara, Yasu, JP;
Tomoyuki Nakamura, Moriyama, JP;
Harunobu Sano, Kyoto, JP;
Takehisa Sasabayashi, Ritto, JP;
Masayuki Ishihara, Yasu, JP;
Tomoyuki Nakamura, Moriyama, JP;
Harunobu Sano, Kyoto, JP;
Murata Manufacturing Co., Ltd., Kyoto-fu, JP;
Abstract
Dielectric ceramic having a high dielectric constant of 5,500 or more and exhibiting good dielectric constant temperature characteristic, and a small, high-capacitance monolithic ceramic capacitor having an electrostatic capacitance temperature characteristic satisfying the X5R characteristic are provided. The dielectric ceramic includes a BaTiObased or (Ba,Ca)TiObased primary component, a rare-earth element and Cu, and has a structure composed of crystal grains and grain boundaries between the crystal grains. The ratio of the average concentration of the rare-earth element in the grain boundaries to the average concentration of the rare-earth element in the inside of the crystal grains is less than 2, and in a cross section of the dielectric ceramic, the rare-earth element is present in 90% or more of the region of first crystal grains, the number of which is 55% to 85% of the crystal grains, and the rare-earth element is present in less than 10% of the region of second crystal grains, the number of which is 15% to 45% of the crystal grains.