Kyocera Corporation

Jun Ueno

Masahiro Nishigaki

Hideyuki Osuzu

Shota Mukoyama

Hiroaki Mino

Masaaki Nagoya

The dielectric layers are formed from a dielectric porcelain formed from crystal particles containing barium titanate as a main component and containing a rare earth element, and the crystal particles have, in a particle boundary vicinity, a low concentration region in which the concentration of the rare earth element is lower than the concentration of the rare earth element in an inside. The crystal particles further contain vanadium, and the low concentration region contains a larger amount of the vanadium than the amount of the vanadium in the inside. The crystal particles further contain magnesium and manganese, and the magnesium and the manganese have a concentration gradient that is at a maximum at the particle boundary vicinity and that lowers toward the inside.

Capacitor

Disclosed is a multilayer ceramic capacitor which is formed by alternately laminating (i) dielectric layers composed of a dielectric ceramic and (ii) internal electrode layers. The dielectric ceramic is composed of crystal grains mainly composed of barium titanate, while containing predetermined amounts of magnesium, vanadium, manganese and terbium, and at least one rare earth element selected from yttrium, dysprosium, holmium and erbium. In an x-ray diffraction chart of the dielectric ceramic, the diffraction intensity of the (200) plane indicating cubic barium titanate is higher than the diffraction intensity of the (002) plane indicating tetragonal barium titanate. The dielectric ceramic has a Curie temperature of 110-120&#xb0; C.

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Kirishima, Japan

Jun Ueno