Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Tadashi Morimoto

Takahiro Yamamoto

Yasuyuki Naito

Hiroshi Komatsu

Harufumi Mandai

Takashi Shikama

Yoichiro Ito

Tetsuya Doi

Yukio Sakabe

Harunobu Sano

Hiroji Tani

Hiroshi Takagi

Norio Nakajima

Yukio Tanaka

Toshio Kawabata

Toru Tominaga

Hiroaki Ichikawa

Kanehito Honma

Masayuki Yamada

Yoshiki Hasegawa

Yoshikazu Yoshida

Shinichi Okubo

Tamio Yamano

Nobumasa Kugutsu

Takuya Miyagawa

Kuniaki Fujimoto

A method of producing a chip inductor including the steps of inserting a conductive wire made of a metallic wire into a metallic mold, supporting both end portions of the conductive wire on support portions provided on inner surfaces of the metallic mold so as to position the conductive wire in the approximate center portion of the metallic mold, casting magnetic ceramic slurry into the metallic mold, molding the ceramic slurry case in the metallic mold by wet pressing to obtain a molding body having the conductive wire embedded therein, firing the molding body, and forming external electrodes on both end surfaces of the fired magnetic core such that the external electrodes are connected to both end portions of the conductive wire.

Method of producing chip inductor

A plurality of feedthrough holes are efficiently formed on the present invention by splitting a laser beam emitted from a laser source into plural laser beams by allowing the beam to pass through a diffraction grating, followed by simultaneously forming a plurality of the feedthrough holes on the ceramic green sheet by irradiating the ceramic green sheet with the split laser beam.

Method for machining ceramic green sheet

An method of manufacturing an inductor having a large current capacity which includes a magnetic sintered body formed via wet pressing treatment and a coil assembly disposed within the magnetic sintered body. The coil assembly is defined by a substantially cylindrical magnetic core member which is wound by a coil. Both ends of the coil of the coil assembly are respectively and electrically connected to an input electrode and an output electrode which are respectively disposed on two mutually facing end surfaces of the magnetic sintered body.

Methods of manufacturing inductors

A method for producing an inductor having an internal conductor includes coating an internal conductor with a covering material, placing the internal conductor coated with the covering material in a shaping mold, and filling a material around the internal conductor so as to form a compact unbaked chip element with the internal conductor provided at a predetermined position. The unbaked chip element is then baked in order to eliminate the covering material so as to form a gap around the internal conductor.

Method for producing an inductor

A ceramic inductor component and a composite component are provided having desired properties, superior stability of properties and superior durability. When Ni&mdash;Cu&mdash;Zn ferrite or Ni&mdash;Cu ferrite is used for a magnetic ceramic body constituting an inductor portion, and when the contents of S, Cl and Na contained in the ferrite are set to be in the ranges of about 5 to 150 ppm, about 5 to 150 ppm and about 5 to 100 ppm, respectively, diffusion of an internal conductive metal primarily composed of Ag into the magnetic ceramic body is suppressed, and hence, the degradation of electric properties can be avoided. Accordingly, by facilitating sintering, the insulating resistance of the ceramic is improved, and the durability and reliability of the ceramic inductor component can be improved.

Ceramic inductor component and composite component using same

A mask is mounted on one surface of a ceramic green sheet which is supported on an X-Y table. The mask is provided with a plurality of through hole transmissive portions. A pulsed laser beam is applied to the mask. The size of the laser beam is sufficiently large to encompass at least several of said through hole transmissive portions. The laser beam passes through the through hole transmissive portions and simultaneously forms a plurality of through holes in the ceramic green sheet. Because the mask is located on (or at least substantially adjacent) the surface of the ceramic green sheet, the size and shape of the through holes will be approximately identical to the size and shape of the through hole transmissive portions, thereby precisely controlling the size and shape of the through holes. The mask can be irradiated while the ceramic green sheet is moving.

Method for forming a through hole in a ceramic green sheet

A method of fabricating a monolithic chip varistor includes the steps of preparing a varistor body including a plurality of varistor layers and at least one pair of internal electrodes; forming a first layer for each of a pair of external electrodes by applying a metal component and a glass component to an exterior portion of the varistor body, followed by heat treatment; forming a second layer for the external electrode on the first layer by applying a glass component, followed by heat treatment; forming a third layer for the external electrode on the second layer by applying a glass component that is different from the glass component used for forming the second layer, followed by heat treatment; forming a fourth layer for the external electrode on the third layer by applying a metal component that is different from the metal component used for forming the first layer, followed by heat treatment under the same heat treatment conditions as those used for the formation of the first layer; and forming a fifth layer for the external electrode by electroplating. During the heat treatment for forming the fourth layer, the metal component contained in the fourth layer is diffused into the second layer and the third layer.

Method of fabricating monolithic varistor

A mask is mounted on one surface of a ceramic green sheet which is supported on an X-Y table. The mask is provided with a plurality of through hole transmissive portions. A pulsed laser beam is applied to the mask. The size of the laser beam is sufficiently large to encompass at least several of said through hole transmissive portions. The laser beam passes through the through hole transmissive portions and simultaneously forms a plurality of through holes in the ceramic green sheet. Because the mask is located on (or at least substantially adjacent) the surface of the ceramic green sheet, the size and shape of the through holes will be approximately identical to the size and shape of the through hole transmissive portions, thereby precisely controlling the size and shape of the through holes. A preferred laser processing apparatus used in this processing method has a laser source, a laser-source driving circuit for driving the laser source, a table for holding an object having a mask disposed thereon, a galvanomirror directed to the table, a galvanomirror driving circuit for changing the reflection angle of the galvanomirror, a control circuit for sending control signals to the laser-source driving circuit and the galvanomirror driving circuit, and a converging lens disposed between the laser source and the mask so as to converge a laser beam emitted from the laser source.

Method and apparatus for forming a through hole in a ceramic green sheet

The present invention provides a system and method for producing a reliable inductor having an internal conductor with a small electric resistance. A metal wire formed in a nonlinear shape is used as the internal conductor. In an exemplary embodiment of the invention, the internal conductor has a coil-like shape with portions adjacent to each other with respect to the axial direction of the coil being positioned in a substantially cylindrical gap formed in the axial direction of the coil. By providing a gap around the internal conductor, stress between the internal conductor and a ceramic material surrounding the conductor can be eliminated. As a result, the characteristic deterioration or crack generation in the inductor chip is eliminated. Moreover, the leakage flux among the coil pitches of the conductor is reduced, thereby improving the characteristics of the inductor.

Inductor and production method thereof

A method of manufacturing a multilayer ceramic electronic component including a step of firing a ceramic green sheet laminate having internal electrodes containing at least one of palladium and silver, and a step of firing the ceramic green sheet laminate in a furnace having an oxygen partial pressure of not more than 5% in a temperature area exceeding 50.degree. C. during a temperature rise from 400.degree. C. to 1100.degree. C.

Method of manufacturing multilayer ceramic electronic component

A dielectric ceramic composition containing 0.3 to 5.0 parts by weight of an additive composed of at least one of SiO.sub.2, Li.sub.2 O and B.sub.2 O.sub.3 per 100 parts by weight of a main component expressed by the following composition formula:

Dielectric ceramic composition

An external electrode is formed on an outer surface of a ceramic molded product. The external electrode consists of an inner layer and an outer layer. The inner layer is composed of conductive material. The outer layer is composed of conductive material and glass material. In a process for producing the ceramic molded product, first, by molding a ceramic material a molded product is formed. On outer surfaces of the molded product, a conductive paste containing copper or the like is coated. Furthermore, on the conductive paste, a conductive paste containing a glass frit is coated. By baking the molded product onto which these two kinds of conductive paste are coated, ceramic electronic parts having an external electrode of 2-layer structure is obtained.

Ceramic electronic part and producing method thereof

A temperature compensating ceramic dielectric of the present invention contains compositions consisting of 2.0 to 14.0 mole % of barium oxide, 51.0 to 63.5 mole % of titanium oxide and 22.5 to 47.0 mole % of neodymium oxide as NdO.sub.3/2. Among the composition range, however, ranges between 2.0 to 9.0 mole % of barium oxide and 60.0 to 63.5 mole % of titanium oxide are to be excluded. By adding 0.1 to 5.0% by weight of niobium oxide as NbO.sub.5/2 to the composition, the temperature compensating ceramic dielectric is obtained.

Temperature compensating ceramic dielectric

A dielectric ceramic composition consists essentially of a main component of a ternary system Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 --Pb(Cu.sub.1/2 W.sub.1/2)O.sub.3 --PbTiO.sub.3, and contains a glass composition with a melting point of 600.degree. to 900.degree. C. in an amount of 0.5 to 1.5 parts by weight per 100 parts by weight of the main component. The main component has a composition represented by the general formula:

A dielectric ceramic composition consists essentially of 80 to 99.7 wt % of a main component of a system, SrTiO.sub.3 -PbTiO.sub.3 -CaTiO.sub.3 -Bi.sub.2 O.sub.3 -TiO.sub.2 -SnO.sub.2, at least one oxide of rare earth elements incorporated therein as an additive in an amount of 0.1 to 5.0 wt % in terms of Re.sub.2 O.sub.3 (where Re is at least one rare element selected from the group consisting of Nd, La, Ce, Pr and Sm), and 0.2 to 15 wt % of a vitreous component. The main component consists essentially of 20.0 to 50.0 wt % of SrTiO.sub.3, 8.0 to 37.6 wt % of PbTiO.sub.3, 3.2 to 33.9 wt % of CaTiO.sub.3, 4.4 to 35.2 wt % of Bi.sub.2 O.sub.3, 2.5 to 13.6 wt % of TiO.sub.2 and 0.2 to 12.0 wt % of SnO.sub.2. The vitreous component consists essentially of 10 to 45 mol % of Li.sub.2 O, 5 to 40 mol % of at least one oxide selected from the group consisting of BaO, MgO, CaO and SrO, 0.2 to 10 mol % of Al.sub.2 O.sub.3, 30 to 70 mol % of at least two oxide selected from the group consisting of SiO.sub.2, MnO.sub.2 and TiO.sub.2, the content of SiO.sub.2 in the vitreous component being not less than 15 mol % at least, and 1 to 35 mol % of CuO.

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Hikone, Japan

Tadashi Morimoto