Murata Manufacturing Co., Ltd.

Toshimi Oguni

Katsutomo Aritomi

Hiroyuki Matsumoto

Hiroaki Kawano

A ceramic green sheet where the proportion of a Si-containing constituent coating the surface of barium titanate-based ceramic particles is 95% or higher, and the proportion of a rare-earth element-containing constituent coating the surface of the barium titanate-based ceramic particle is 85% or higher.

Ceramic green sheet, method for manufacturing multilayer ceramic capacitor, and multilayer ceramic capacitor

A method for producing a multilayer ceramic capacitor that includes preparing a dielectric ceramic material by mixing a perovskite compound, a Re compound, a Mn compound, a Mg compound, and a Si compound. The perovskite compound contains Ba and Ti and has 1.2&#xd7;10or more and 4.5&#xd7;10or less Ba vacancies per gram. Re in the Re compound is at least one element selected from Y, Gd, Tb, Dy, Ho, Er, and Yb. Green sheets containing the dielectric ceramic material are then formed. Inner electrode patterns are then formed on some of the green sheets. An unsintered capacitor body is then formed by stacking the green sheets, some of which have the inner electrode patterns formed thereon. Sintering of the unsintered capacitor body is then conducted.

Method for producing multilayer ceramic capacitor

A method of manufacturing a ceramic capacitor component that includes preparing a laminate body including first to third green sheets by stacking the first green sheets before applying conductive paste, stacking the second green sheets with conductive paste applied thereon on the first green sheets, and stacking the third green sheets before applying conductive paste on the second green sheets; preparing fourth green sheets from a raw material that does not contain VO; providing the fourth green sheets onto four surfaces of the laminate body other than end surfaces of the laminate body to form a main body; firing the main body; and applying and baking a Cu paste onto the four surfaces of the main body and the end surfaces of the main body.

Laminated ceramic capacitor

When a voltage two times a rated voltage is applied between a first external electrode and a second external electrode of a ceramic capacitor, the electric field intensity generated at portion connected between a first internal electrode and an end of a portion of a second external electrode at a side of a first side surface by a shortest distance Fis about 0.34 kV/mm or less.

Ceramic capacitor having a small variation in capacity

A multilayer ceramic capacitor includes a ceramic laminated body including dielectric ceramic layers and internal electrodes stacked with the dielectric ceramic layers disposed therebetween. The dielectric ceramic layers contain a perovskite compound containing Ba and Ti, Zr, and a rare earth element, and ratios of Zr and the rare earth element to 100 molar parts of Ti are about 0.4 to 2.0 molar parts and about 0.05 to 0.5 molar parts, respectively. The molar ratio of Zr to the rare earth element is about 3.3 to about 8.0, and Al-containing segregated substances are present in about 80% or more of defective portions where continuity of the internal electrodes is interrupted. Dielectric ceramic constituting the dielectric ceramic layers has an average grain diameter of about 230 nm to about 350 nm.

Multilayer ceramic capacitor

A laminated ceramic capacitor that includes dielectric layers stacked adjacent one another to form a laminated body; internal electrodes arranged between the dielectric layers; external electrodes along surfaces of the laminated body and connected to the internal electrodes; and a covering layer covering at least portions of sections of the laminated body between the laminated body and edges of the external electrodes. The external electrodes include a silver-containing layer containing at least Ag as its main constituent. The dielectric layers and the covering layercontain, as their main constituent, a perovskite compound represented by a chemical formula ABO, wherein A is at least one of Ba, Sr, and Ca, and B is at least one of Ti, Zr, and Hf. V is added to only the dielectric layers among the dielectric layers and the covering layer.

Laminated ceramic capacitor having a covering layer

An electronic component includes an electronic component body, first and second outer electrodes, and first and second inner electrodes. The first outer electrode includes a first conductive layer that does not include silver and a second conductive layer that is deposited on the first conductive layer so as to be positioned at an outermost layer and that includes silver. The second conductive layer includes a first contact portion in contact with a first main surface and is not in contact with first and second side surfaces. A first inner conductor is provided on a virtual straight or substantially straight line connecting a second inner electrode closest to the first contact portion and the first contact portion in the shortest distance. The first inner conductor is connected only to the first outer electrode or is connected to none of the first and second outer electrodes.

Electronic component

A laminated ceramic capacitor has a high breakdown voltage and excellent withstand-voltage performance, and prevents cracks generated during firing even when the number of lamination layers constituted by ceramic layers and inner electrode layers is increased. The laminated ceramic capacitor includes capacitance forming layers in which ceramic dielectric layers and capacitance-forming inner electrode layers are laminated, and a stress relieving layer. The stress relieving layer is disposed between the capacitance forming layers. In the stress relieving layer, ceramic dielectric layers, dummy inner electrode layers (split electrodes) that do not contribute to the formation of electrostatic capacitance, and capacitance-formation-preventing inner electrode layers that prevent capacitance from being formed between the capacitance-forming inner electrode layers and the dummy inner electrode layers are laminated. The thickness of the stress relieving layer is in the range of about 100 &#x3bc;m to about 300 &#x3bc;m inclusive. The plane area of the dummy inner electrode layers is about 60% or more of that of the capacitance-forming inner electrode layers. The dummy inner electrode layers are undivided or are divided into two or three parts in a single layer. With this structure, stress caused by electrostriction is relieved.

Growing community of inventors

Nagaokakyo, Japan

Toshimi Oguni