Tdk Corporation

Tomohiro Arashi

Yasuharu Miyauchi

Toshio Sakurai

Hisashi Kobuke

Takeshi Nomura

Yukie Nakano

Takahiro Nakano

Kiyoshi Hatanaka

Akira Sato

Kyung-Ku Choi

Atsushi Hitomi

Akira Satoh

Raitarou Masaoka

Tomoko Nakamura

Osamu Taguchi

Tomoaki Kawata

Junko Yamamatsu

Naoki Kawano

A dielectric ceramic composition is represented by a general formula 'xBiO.yZnO.(z-a)NbO.aVO'. The variables, 'x', &#x201c;y&#x201d;, &#x201c;z&#x201d; and &#x201c;a&#x201d; in the general formula respectively satisfy the following conditions: 2.90&#x2266;x&#x2266;3.10, 1.90&#x2266;y&#x2266;2.10, 1.90&#x2266;z&#x2266;2.10, and 0.0005&#x2266;a&#x2266;0.020.

[object Object]

A ceramic electronic component includes a first dielectric layer, a second dielectric layer, and a boundary reaction layer. The first dielectric layer is a layer containing BaO, NdO, and TiO, the second dielectric layer is a layer containing a material different from the material of the first dielectric layer, and the boundary reaction layer is a layer formed between the first dielectric layer and the second dielectric layer and containing at least one of Zn, Ti, Cu, and Mg.

Ceramic electronic component and method of manufacturing ceramic electronic component

A dielectric ceramic composition includes a component represented by composition formula {&#x3b1;(xBaO.yNdO.zTiO)+&#x3b2;(2MgO.SO)} as a main component and zinc oxide, boron oxide, and a glass having a softening point equal to or lower than a certain temperature as minor components with respect to the main component. In the dielectric ceramic composition, x, y, and z that respectively represent molar ratios of BaO, NdO, and TiOare in certain ranges and &#x3b1; and &#x3b2; that represent volume ratios of subcomponents (xBaO.yNdO.zTiOand 2MgO.SiO) in the main component are in certain ranges. When the minor components are respectively represented by aZnO, bBO, and cglass, a, b, and c that represent mass ratios of the respective minor components to the main component are in certain ranges.

Dielectric ceramic composition

Provided is a dielectric ceramic that includes a main component which contains MgSiOand additives which contain a zinc oxide and a glass component, in which, in X-ray diffraction. The peak intensity ratio, I/I, of the X-ray diffraction peak intensity Iof zinc oxide remaining unreacted, for which 2&#x3b8; is between 31.0&#xb0; and 32.0&#xb0; and between 33.0&#xb0; and 34.0&#xb0;, with respect to the peak intensity Iof MgSiOas the main phase, for which 2&#x3b8; is between 36.0&#xb0; and 37.0&#xb0;, is 10% or less. The dielectric ceramic has a relative density of 96% or greater.

Dielectric ceramic, method for producing dielectric ceramic, and electronic component

A ceramic electronic component includes a first dielectric layer, a second dielectric layer, and an intermediate layer. The first dielectric layer is a layer containing BaO, NdO, and TiO, the second dielectric layer is a layer containing a different material from the material of the first dielectric layer, and the intermediate layer is a layer formed between the first dielectric layer and the second dielectric layer and containing main components that are not contained in the first dielectric layer and the second dielectric layer in common as the main components.

To provide a dielectric ceramic composition which is free from variation in breakdown voltage, and has excellent electric properties. The dielectric ceramic composition according the present invention includes: as a main component, a component represented by a composition formula {&#x3b1;(xBaO-yNdO-zTiO)+&#x3b2;(2MgO&#x2014;SiO)}, wherein x, y, and z representing a molar ratio of the BaO NdO, and TiOare each in a specific molar ratio range, and &#x3b1; and &#x3b2; representing a volume ratio of each component, zinc oxide, boron oxide, a glass having a softening point at a specific temperature or less, and silver, wherein a, b, c, and d representing a mass ratio of each of the minor components based on the main component are each in a specific mass ration range.

A dielectric porcelain composition here contains as main components BaO, NdO, TiO, MgO and SiOat the given ratios and as subordinate components ZnO, BO, CuO and an alkaline earth metal oxide RO (R: an alkaline earth metal) at given ratios, preferably with the addition of Ag as an optional subordinate component, so that it can have low-temperature sintering capability stable and reliable enough to permit a conductor formed of Ag, an alloy containing Ag as a main component or the like to be used as an internal conductor.

Dielectric porcelain composition and method for production thereof

A dielectric porcelain composition here contains as main components BaO, NdO, TiO, MgO and SiOat the given ratios and as subordinate components ZnO, BOand CuO at given ratios, so that it can have a low-temperature sintering capability stable and reliable enough to permit a conductor formed of Ag, an alloy containing Ag as a main component or the like to be used as an internal conductor. It is also possible to obtain a dielectric porcelain composition that has limited resonance frequency changes with temperature changes and a specific dielectric constant lower than that of a BaO-rare earth oxide-TiObase dielectric porcelain composition, and so is suitable for multilayer type device formation.

Objects of the present invention are to provide a low-temperature co-fired ceramic material having a coefficient of linear thermal expansion controlled and has a high dielectric constant, and to reduce the warpage of a fired product even if it has an unsymmetrical lamination structure in a multilayer wiring board in which glass-ceramic mixed layers of different compositions are laminated. A low-temperature co-fired ceramic material in accordance with the present invention includes: SiO&#x2014;BO&#x2014;AlO&#x2014; alkaline earth metal oxide based glass, alumina, titania, and cordierite; glass, titania, and cordierite; or glass, titania, and mullite. When a multilayer wiring board is made of the low-temperature co-fired ceramic material, the content of cordierite or mullite of the substrate material is adjusted to control a difference in a coefficient of linear thermal expansion between the layers of the substrate material to not more than 0.25&#xd7;10/&#xb0; C.

Low-temperature co-fired ceramics material and multilayer wiring board using the same

A dielectric porcelain composition includes MgTiOand MgSiOand satisfies a+b=1 and 0&#x3c;b&#x3c;1, wherein a denotes a molar ratio of MgTiOand b denotes a molar ratio of MgSiO. It can include MgTiOand CaTiOand satisfy a+c=1 and 0&#x3c;c&#x2266;0.15, wherein a has the same meaning as shown above and c denotes a molar ratio of CaTiO. It can also include MgTiO, MgSiOand CaTiOand satisfy a+b+c=1, 0&#x3c;b&#x3c;1 and 0&#x3c;c&#x2266;0.15, wherein a, b and c have the same meanings as shown above. These compositions can be manufactured, with the content of MgSiO, the content of CatiOand the contents of MgSiOand CaTiOadjusted, respectively. These compositions can be used as dielectric materials to manufacture dielectric resonators.

Dielectric porcelain composition and dielectric resonator using the composition

A multilayer varistor comprising a varistor chip body having alternately stacked ceramic layers and internal electrode layers is provided. The ceramic layer is composed of a composite oxide containing Ti and/or Zr and Ba as a main component and Si and/or Al as a subordinate component, substantially free of Cr, and has a perovskite phase. The internal electrode layer is composed of a conductor containing a base metal such as Ni or Ni alloy as a main component. The varistor is used in an electric circuit for suppressing noise.

Multilayer varistor

The invention provides a multilayer ceramic chip capacitor which satisfies X7R property or a temperature response of its capacitance and shows a minimal change of capacitance with time under a DC electric field, a long accelerated life of insulation resistance (IR) and good DC bias performance and also provides a multilayer ceramic chip capacitor which is resistant to dielectric breakdown in addition to the above advantages. In a first form of the invention, dielectric layers contain BaTiO.sub.3 as a major component and MgO, Y.sub.2 O.sub.3, at least one of BaO and CaO, and SiO.sub.2 as minor components in a specific proportion. In a second form, the dielectric layers further contain MnO and at least one of V.sub.2 O.sub.5 and MoO.sub.3 as minor components in a specific proportion. In the first form, the dielectric layer has a mean grain size of up to 0.45 .mu.m, and in an X-ray diffraction chart of the dielectric layer, a diffraction line of (200) plane and a diffraction line of (002) plane at least partially overlap one another to form a wide diffraction line which has a half-value width of up to 0.35.degree..

Multilayer ceramic chip capacitor

A multilayer ceramic chip capacitor includes alternately stacked dielectric layers and internal electrode layers. The dielectric layers contain barium titanate as a major component and magnesium oxide, manganese oxide, barium oxide and/or calcium oxide, silicon oxide and optionally, yttrium oxide as minor components in such a proportion that there are present 0.1-3 mol of MgO, 0.05-1.0 mol of MnO, 2-12 mol of BaO+CaO, 2-12 mol of SiO.sub.2 and up to 1 mol of Y.sub.2 O.sub.3 per 100 mol of BaTiO.sub.3. The capacitor satisfies the standard temperature dependence of capacitance and shows a minimized change of capacitance with time under an applied DC electric field and a long insulation resistance life. Where the dielectric layers contain 0.1-3 mol of MgO, 1-5 mol of Y.sub.2 O.sub.3, 2-12 mol of BaO+CaO, and 2-12 mol of SiO.sub.2 per 100 mol of BaTiO.sub.3, the capacitor shows improved DC bias performance.

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Tokyo, Japan

Tomohiro Arashi