Tdk Corporation

Kaname Ueda

Takahiro Itami

Katsunari Moriai

Hitoshi Ishida

Naoyoshi Yoshida

Akira Saitoh

Yasushi Izumibe

Ryou Kobayashi

Hitoshi Tanaka

Takashi Fukui

Akira Yamaguchi

Takashi Kamiya

Akira Sato

Dai Matsuoka

Satoshi Goto

Tatsuya Kojima

Shogo Murosawa

Toru Tonogai

Yusuke Imai

Masayuki Uchida

Takeshi Yanata

Raitaro Masaoka

Shintaro Kon

Takeshi Oyanagi

Naoki Chida

Izuru Soma

Daiki Suzuki

Shin Kagaya

Akinori Iwasaki

Hisayoshi Saito

Arata Sato

Osamu Otani

Syunichi Yuri

A multilayer chip varistor includes an element body, first and second external electrodes, and first and second electrical conductor groups. The first electrical conductor group includes a first internal electrode connected to the first external electrode, and a first intermediate electrical conductor opposed to the first internal electrode. The second electrical conductor group includes a second internal electrode including a first electrically conductive material and connected to the second external electrode, and a second intermediate electrical conductor opposed to the second internal electrode. At least one of the first and second intermediate electrical conductors includes the second electrically conductive material. The element body includes a low electrical resistance region between the first and second internal electrodes. The second electrically conductive material is diffused in the low electrical resistance region.

Multilayer chip varistor

A nonlinear resistor ceramic composition includes zinc oxide as main component, and, as subcomponents, with respect to 100 mol of zinc oxide in terms of respective elements, more than 0.05 to less than 30 at. % of oxide of Co, more than 0.05 to less than 20 at. % of oxide of Sr, more than 0.01 to less than 20 at. % of oxides of rare earth except for Sc and Pm, more than 0.01 to less than 10 at. % of oxide of Si and does not include Al, Ga and In. Alternatively, a nonlinear resistor ceramic composition includes zinc oxide as main component, and, as subcomponents, with respect to 100 mol of zinc oxide in terms of respective elements, more than 0.05 at. % and less than 30 at. % of an oxide of Co, more than 0.05 to less than 20 at. % of oxide of Sr, more than 0.01 to less than 20 at. % of oxides of rare earth except for Sc and Pm, more than 0.01 to less than 10 at. % of oxide of Si and more than 0.01 to less than 10 at. % of calcium zirconate in terms of CaZrO. By the present invention, deviations of various characteristics can be made small and grain growth of grains is suppressed with lowering CV product.

Nonlinear resistor ceramic composition and electronic component

A voltage nonlinear resistor ceramic composition comprises zinc oxide, with respect to 100 mol of said zinc oxide, 0.30 to 10 mol of Co oxide in terms of Co, 0.10 to 10 mol of R oxide (note that R is at least one selected from a group consisting of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) in terms of R, 0.10 to 5 mol of Cr oxide in terms of Cr, 0.10 to 5 mol of oxide of at least one selected from Ca and Sr respectively in terms of Ca or Sr, 0.0005 to 5 mol of oxide of at least one selected from Al, Ga and In respectively in terms of Al, Ga or In, and 0.10 to 5 mol of barium titanate in terms of BaTiO.

Voltage nonlinear resistor ceramic composition and electronic component

A chip varistor is provided with a varistor section and a plurality of terminal electrodes. The varistor section is comprised of a sintered body containing ZnO as a major component, exhibits the nonlinear voltage-current characteristics, and has a pair of principal surfaces opposed to each other. The plurality of terminal electrodes are connected each to the varistor section. Each of the terminal electrodes has a first electrode portion connected to either of the principal surfaces and a second electrode portion connected to the first electrode portion.

Chip varistor

A chip varistor is provided with a varistor section, a plurality of electroconductive sections, and a plurality of terminal electrodes. The varistor section is comprised of a sintered body containing ZnO as a major component and is configured to exhibit the nonlinear voltage-current characteristics. The plurality of electroconductive sections are comprised of sintered bodies containing ZnO as a major component and arranged with the varistor section in between, and each electroconductive section has a first principal surface connected to the varistor section and a second principal surface opposed to the first principal surface. The plurality of terminal electrodes are connected respectively to the corresponding electroconductive sections. Each terminal electrode has a first electrode portion connected to the second principal surface and a second electrode portion connected to the first electrode portion.

A chip varistor is provided with a varistor section, a plurality of electroconductive sections, and a plurality of terminal electrodes. The varistor section is comprised of a sintered body containing ZnO as a major component and exhibits the nonlinear voltage-current characteristics. The plurality of electroconductive sections are arranged on both sides of the varistor section and each electroconductive section has a first principal surface connected to the varistor section and a second principal surface opposed to the first principal surface. The terminal electrodes are connected to the respective second principal surfaces of the electroconductive sections.

Chip varistor and chip varistor manufacturing method

A chip-type electronic component has: a ceramic element body; a plurality of first and second internal electrodes arranged in the ceramic element body so as to be opposed at least in part to each other; a first external connection conductor to which the plurality of first internal electrodes are connected; a second external connection conductor to which the plurality of second internal electrodes are connected; first and second terminal electrodes; a first internal connection conductor arranged in the ceramic element body and connecting the first external connection conductor and the first terminal electrode; and a second internal connection conductor arranged in the ceramic element body and connecting the second external connection conductor and the second terminal electrode. The number of the first internal connection conductor is set to be smaller than the number of the first internal electrodes and the number of the second internal connection conductor is set to be smaller than the number of the second internal electrodes.

Chip-type electronic component

A method of production of a multilayer ceramic electronic device having dielectric layers with an interlayer thickness of 5 &#x3bc;m or less and internal electrode layers including a base metal, including the steps of firing, then annealing a stack comprised of a dielectric layer paste and an internal electrode layer paste including a base metal alternately arranged in 100 layers or more under a reducing atmosphere, treating the annealed stack by first heat treatment under a strong reducing atmosphere of an oxygen partial pressure Pof over 2.9&#xd7;10Pa to less than 6.7&#xd7;10Pa at a holding temperature Tof over 300&#xb0; C. to less than 600&#xb0; C. The stack after the first heat treatment is treated by second heat treatment under an atmosphere of an oxygen partial pressure Pof over 1.9&#xd7;10Pa to less than 4.1&#xd7;10Pa at a holding temperature Tof over 500&#xb0; C. to less than 1000&#xb0; C.

Method of production of multilayer ceramic electronic device

Internal electrode layers are superimposed in a dielectric substrateat intervals. Step absorption layers are respectively provided on lateral sides of the internal electrode layers. A side portion of the internal electrode layer forms an inclined surface, and the step absorption layer is superimposed so as to partially overlap the inclined surface of the internal electrode layer. This is also applied to the other internal electrode layers and step absorption layers.

Multilayer electronic component and manufacturing method thereof

A method of production of a ceramic electronic device such as a multilayer ceramic capacitor, comprising forming a first ceramic coating layer on the surface of a substrate, forming an internal electrode on the surface of the first ceramic coating layer, then forming a second ceramic coating layer on the surface of the first ceramic coating layer so as to cover the internal electrode. In this case, when a mean particle size of ceramic particles of the first ceramic coating layer is &#x3b1;, a thickness of the first ceramic coating layer is T, a mean particle size of ceramic particles of the second ceramic coating layer is &#x3b1;, and a thickness of the second ceramic coating layer is T, the conditions of &#x3b1;, 0.05&#x3c;&#x3b1;&#x2266;0.35 &#x3bc;m, T&#x3c;T, and 0&#x3c;T&#x3c;1.5 &#x3bc;m are satisfied. As a result, it is possible to provide a ceramic electronic device, in particular a multilayer ceramic capacitor, resistant to short-circuit defects, withstand voltage defects, and other structural defects.

Ceramic electronic device and method of production of same

A ceramic powder including ceramic main component particles and additive component particles deposited on the surfaces of the main component particles. The mean particle size of the main component particles is made not more than 1.5 &#x3bc;m, and the mean particle size of the additive component particles is made not more than 0.31 &#x3bc;m. The content of the additive composition particles is made 0.1 to 5 wt % with respect to 100 parts by weight of the ceramic powder. The dispersibility of the additive component particles with respect to the main component particles is improved and the uniformity of the structure is promoted to suppress the occurrence of hetero phases. A multilayer ceramic electronic device having a high insulation breakdown voltage and long life even with a thickness of the dielectric layers of not more than 3 &#x3bc;m are provided.

Ceramic powder and multilayer ceramic device

A method of production of a ceramic electronic device such as a multilayer ceramic capacitor, comprising forming a first ceramic coating layer on the surface of a substrate, forming an internal electrode on the surface of the first ceramic coating layer, then forming a second ceramic coating layer on the surface of the first ceramic coating layer so as to cover the internal electrode. In this case, when a mean particle size of ceramic particles of the first ceramic coating layer is &agr;1, a thickness of the first ceramic coating layer is T1, a mean particle size of ceramic particles of the second ceramic coating layer is &agr;2, and a thickness of the second ceramic coating layer is T2, the conditions of &agr;1&lE;&agr;2, 0.05<&agr;1&lE;0.35 &mgr;m, T1<T2, and 0<T1<1.5 &mgr;m are satisfied. As a result, it is possible to provide a ceramic electronic device, in particular a multilayer ceramic capacitor, resistant to short-circuit defects, withstand voltage defects, and other structural defects.

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Tokyo, Japan

Kaname Ueda