Taiyo Yuden Co., Ltd.

Taiyo Yuden Kabusikigaisha

Taiyo Yuden Kabushikigaisha

Hisamitsu Shizuno

Hiroshi Kishi

Hirokazu Chazono

Hiroshi Saito

Mutsumi Honda

Minoru Oshio

Toshiya Nakamura

Kenji Saito

Keisuke Ishii

Yasunobu Kawamoto

Takayuki Hattori

Takashi Asai

Yuto Yamato

Hirosi Saito

Hirosi Kisi

Koichiro Morita

Makoto Fujii

Youichi Mizuno

Katsuhiko Arai

Shinya Kusumi

Yuji Nishi

A multi-layer ceramic capacitor having a weight of 8 mg or more includes a capacitance forming unit and a protective unit. The capacitance forming unit includes internal electrodes that are laminated in a first direction and includes end portions, positions of the end portions in a second direction orthogonal to the first direction being aligned with one another within a range of 0.5 &#x3bc;m in the second direction. The protective unit covers the capacitance forming unit in the first direction and the second direction and includes an outer surface, a shortest distance between the outer surface and the end portion of an outermost layer in the internal electrodes in the first direction exceeding 10 &#x3bc;m.

Multi-layer ceramic capacitor

A multilayer displacement element is formed by alternately stacking a plurality of ceramic layers and a multiplicity of internal electrodes, wherein each of the ceramic layers is composed of ceramic grains containing barium titanate as a main component and each of the internal electrodes is a metallic film with a mesh shape. The meshed shape of metallic films leads to a reduced contact area between the metallic films and the ceramic layers. Therefore, the displacement of the ceramic layers can be less restricted by the metallic films and thus the amount of displacement of the ceramic layers can be increased. The ceramic grains preferably have an average diameter equal to or larger than 3.5 &#x3bc;m and it is desirable that the ratio of one grain to one layer for the ceramic layer be equal to or larger than 20%.

Multilayer displacement element

A method for manufacturing a multilayer ceramic capacitor includes the steps of forming a ceramic slurry, forming ceramic green sheets from the ceramic slurry, printing internal electrode patterns on the ceramic green sheets, generating a laminated body by stacking the ceramic green sheets provided with the internal electrode patterns printed thereon, dicing the laminated body to thereby form chip-shaped ceramic bodies and sintering the chip-shaped ceramic bodies. The ceramic slurry includes a glass component containing one or more additive elements selected from the group consisting of Mn, V, Cr, Mo, Fe, Ni, Cu and Co.

Method for manufacturing a multilayer ceramic capacitor

A multilayer ceramic capacitor includes sintered laminated bodies having a plurality of dielectric layers alternately stacked with a multiplicity of internal electrodes, and a pair of external electrodes electrically coupled to the internal electrodes. The dielectric layer is of sintered ceramic grains. The ceramic grains include a core portion surrounded by a shell portion or a solid solution. The ceramic grains contain additive elements such as acceptor elements and/or rare earth elements. The additive elements are non-uniformly distributed in the core and/or shell portion of the ceramic grain or in the solid solution. Such non-uniform distribution of the additive elements in ceramic grains promotes or facilitates the re-oxidation process of the ceramic grains and also increases electrical resistance thereof. Accordingly, the operating life characteristics of the multilayer ceramic capacitors, especially those incorporating therein thin dielectric layers, can be improved.

Multilayer ceramic capacitor and method for the manufacture thereof

A multilayer ceramic capacitor is formed by alternately stacking a plurality of dielectric layers and a multiplicity of internal electrodes, which are connected to a pair of external electrodes. Each of the dielectric layers is obtained from a dielectric ceramic compound composed of ceramic grains and a glass component connecting the ceramic grains, and the glass component contains one or more additive elements in a form of a solid solution. The additive elements are selected from the group consisting of Mn, V, Cr, Mo, Fe, Ni, Cu and Co.

Multilayer ceramic capacitor and method for manufacturing same

The ceramic capacitor in accordance with the present invention is fabricated by employing a dielectric ceramic composition in forming dielectric layers thereof, wherein the dielectric ceramic composition contains an oxide of Ba and Ti, an oxide of Re (Re used herein represents one or more rare-earth elements selected from Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Tb and Y), an oxide of Mg, one or more oxides selected from oxides of Mn, V and Cr, an oxide of Mo and/or W and SiO or a glass component including SiO , wherein the amount of the oxide of Ba and Ti is 100 mol % in terms of BaTiO , the amount of the oxide of Re is 0.25 to 1.5 mol % in terms of Re O , the amount of the oxide of Mg is 0.2 to 1.5 mol % in terms of MgO and the amount of one or more oxides of Mn, V or Cr is 0.03 to 0.6 mol % in terms of Mn O , V O , Cr O , respectively, and the amount of the oxide of Mo and/or W is 0.025 to 0.25 mol % in terms of MoO and WO .

Dielectric ceramic composition and ceramic capacitor

A multilayer ceramic capacitor includes sintered laminated bodies having a plurality of dielectric layers alternately stacked with a multiplicity of internal electrodes, and a pair of external electrodes electrically coupled to the internal electrodes. The dielectric layer is of sintered ceramic grains. The ceramic grains include a core portion surrounded by a shell portion or a solid solution. The ceramic grains contain additive elements such as acceptor elements and/or rare earth elements. The additive elements are non-uniformly distributed in the core and/or shell portion of the ceramic grain or in the solid solution. Such non-uniform distribution of the additive elements in ceramic grains promotes or facilitates the re-oxidation process of the ceramic grains and also increases electrical resistance thereof. Accordingly, the operating life characteristics of the multilayer ceramic capacitors, especially those incorporating therein thin dielectric layers, can be improved. As a result, the thickness of dielectric layers can be further reduced and a greater number of dielectric layers can be used in forming multilayer ceramic capacitors, enabling miniaturization and large capacitance thereof to be achieved.

A multilayer ceramic capacitor includes a multilayer ceramic body having alternately stacked ceramic layers and internal electrodes, the ceramic layers containing therein an acceptor representing one or more metallic elements for facilitating a reoxidation process of the multilayer ceramic body, and a pair of external electrodes installed at two opposite sides of the multilayer ceramic body, wherein the acceptor concentration in the ceramic layers stacked at a central portion of the multilayer ceramic body is higher than that in the remaining ceramic layers of the multilayer ceramic body.

The ceramic capacitor in accordance with the present invention is fabricated by employing a dielectric ceramic composition in forming dielectric layers thereof, wherein the dielectric ceramic composition contains an oxide of Ba and Ti, an oxide of Re (Re used herein represents one or more rare-earth elements selected from Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Tb and Y) and one or more oxides selected from oxides of Mn, V and Cr, wherein the amount of the oxide of Ba and Ti is 100 mol % in terms of BaTiO , the amount of the oxide of Re is 0.25 to 1.5 mol % in terms of Re O and the amount of one or more oxides of Mn, V or Cr is 0.03 to 0.6 mol % in terms of Mn O , V O , Cr O , respectively, wherein the ratio of Ba to Ti ranges between 0.970 and 1.030.

Ceramic composition and ceramic capacitor

A miniaturized ceramic capacitor having excellent electric characteristics and substantial capacity can be obtained by firing under a non-oxidative atmosphere at a temperature of up to 1200.degree. C. A dielectric layer of this ceramic capacitor consists of a basic component of 100 parts by weight and an additional component of 0.2 to 5 parts by weight. The basic component consists essentially of a material represented by the following formula:

Ceramic capacitor and method for fabricating the same

Disclosed is a ceramic capacitor of a mono-layer structure or a multi-layer structure, which has characteristic X7R (characteristic B) and which is high in reliability in direct current breakdown voltage at 125.degree. C. and small in size. The ceramic capacitor has a dielectric layer and internal electrodes disposed so as to interpose the dielectric layer. The dielectric layer is composed of a sintered body of ceramic particles whose core sections are made mainly of BaTiO.sub.3 and whose shell sections are made from BaTiO.sub.3 in the form of a solid solution composed of an oxide of one or more than one element selected from Mg, Ca, Sr and Zn and an oxide of one or more than one element selected from Sc, Y, Gd, Dy, Ho, Er, Yb, Tb, Tm and Lu.

Ceramic capacitor and method for the preparation thereof

A monolithic capacitor having a dielectric ceramic body cosintered with at least two base metal electrodes. The ceramic body is composed of a major ingredient expressed by the formula,

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Takasaki, Japan

Hisamitsu Shizuno