Tdk Corporation

Yo Saito

Makoto Numata

Hiroyuki Sato

Hitoshi Tanaka

Goro Takeuchi

Dai Matsuoka

Ryuichi Tanaka

Kouki Yamada

Jitsuo Kanazawa

Katsunari Moriai

Daisuke Tsuchida

Izuru Soma

Takashi Inagaki

Hitoshi Ishida

Takahiro Itami

Takeshi Yanata

Osamu Taguchi

Takeshi Oyanagi

Hideaki Sone

Kazuto Takeya

Kimio Suto

Yukihiro Murakami

Nobuei Shimojo

A piezoelectric device has: a ceramic substrate having a first principal surface and a second principal surface opposed to each other; a piezoelectric element arranged on the first principal surface; a frame having a first face and a second face opposed to each other and arranged on the ceramic substrate so as to surround the piezoelectric element; a metal layer arranged on the second face of the frame; and a metal lid arranged on the metal layer so as to close a space surrounded by the frame. The first face of the frame is in contact with the first principal surface of the ceramic substrate. The metal layer and the metal lid are joined to each other by resistance welding. The frame has a composite portion containing a metal and a metal oxide and the composite portion includes the second face and is in contact with the metal layer.

Piezoelectric device

Provided is a piezoelectric device capable of improving measurement precision of a temperature of a piezoelectric element. A piezoelectric device () includes a package () including a housing member () having a thermistor substrate () and a frame () provided to project from a first main surface () of the thermistor substrate () and in which a housing part () is formed by the first main surface () and the frame () and a lid () provided on the frame () to cover a space () of the housing part (), and a piezoelectric vibration element () provided on the first main surface () of the thermistor substrate () in the housing part (), wherein the thermistor substrate () is a multilayer negative temperature coefficient (NTC) thermistor.

Temperature compensated piezoelectric oscilator device package wherein the base of the package consists of a multilayer thermistor

A chip thermistorhas a thermistor portioncomprised of a ceramic material containing respective metal oxides of Mn, Ni, and Co as major ingredients; a pair of composite portionscomprised of a composite material of Ag&#x2014;Pd, and respective metal oxides of Mn, Ni, and Co and arranged on both sides of the thermistor portionso as to sandwich in the thermistor portionbetween the composite portions; and external electrodesconnected to the pair of composite portions, respectively. In this manner, the pair of composite portionsare used as bulk electrodes and, for this reason, the resistance of the chip thermistorcan be adjusted mainly with consideration to the resistance in the thermistor portion, without need for much consideration to the distance between the external electrodesand other factors.

Chip thermistor and method of manufacturing same

A chip thermistor includes a thermistor element body and a pair of outer electrodes. The thermistor element body has a pair of end faces opposing each other and a main face connecting the end faces to each other. The pair of outer electrodes are arranged on the pair of end faces, respectively. The pair of outer electrodes have a width in a direction intersecting the opposing direction of the pair of end faces made narrower with distance from the thermistor element body.

Chip thermistor

A chip thermistor is provided with a thermistor element body, a first electrode, a second electrode, and a third electrode. The thermistor element body has a first principal face and a second principal face opposed to each other in a first direction. The first electrode and the second electrode are arranged as separated from each other in a second direction perpendicular to the first direction, on the first principal face of the thermistor element body. The third electrode is arranged so as to lap over the first electrode and the second electrode, when viewed from the first direction, on the second principal face of the thermistor element body.

Chip thermistor and thermistor assembly board

A chip thermistor has a thermistor portion including a ceramic material containing respective metal oxides of Mn, Ni, and Co as major ingredients; a pair of composite portions including a composite material of Ag&#x2014;Pd, and respective metal oxides of Mn, Ni, and Co and arranged on both sides of the thermistor portion so as to sandwich in the thermistor portion between the composite portions; and external electrodes connected to the pair of composite portions, respectively. In this manner, the pair of composite portions are used as bulk electrodes and, for this reason, the resistance of the chip thermistor can be adjusted mainly with consideration to the resistance in the thermistor portion without need for much consideration to the distance between the external electrodes and other factors.

An aggregate substrate has a first varistor part, a second varistor part, and a heat dissipation layer. The first varistor part includes a first varistor element layer to exhibit nonlinear voltage-current characteristics, and a plurality of first internal electrodes juxtaposed in the first varistor element layer. The second varistor part includes a second varistor element layer to exhibit nonlinear voltage-current characteristics, and a plurality of second internal electrodes juxtaposed in the second varistor element layer. The heat dissipation layer is located between the first and second varistor parts and is in contact with the first and second varistor parts.

Aggregate substrate, production method of aggregate substrate, and varistor

A varistor having a favorable heat-dissipating property is provided. In the varistor, a composite part having a favorable heat-dissipating property formed by a composite material composed of ZnO and Ag is arranged between main faces of a varistor matrix. Therefore, the heat transmitted from a semiconductor light-emitting device to a varistor part through an outer electrode can rapidly be transferred toward a main face on the opposite side through the composite part. In this varistor, side faces excluding inner side faces are exposed at side faces of the varistor matrix. Such a structure yields a favorable heat-dissipating property.

Varistor

A first varistor section includes a first face of an element body, and a third face facing the first face. The first varistor section has a first varistor element body, a first varistor electrode electrically connected to a first external electrode, and a second varistor electrode electrically connected to a second external electrode. A heat radiation section has a first heat radiation portion kept in contact with the third face of the first varistor section and electrically connected to the first and third external electrodes, a second heat radiation portion kept in contact with the third face of the first varistor section and electrically connected to the second and fourth external electrodes, and an insulating layer located between the first heat radiation portion and the second heat radiation portion and electrically insulating the first heat radiation portion and the second heat radiation portion from each other. The first heat radiation portion and the second heat radiation portion contain a metal.

In a varistor, a heat radiating portion contains the same components as ZnO that is the main component of a varistor element body, as metal oxides, thereby, the structural components of the varistor element body and the heat radiating portion are caused to be common. During firing, Ag contained in the heat radiating portion diffuses into the grain boundaries of ZnO, near the interface between surfaces of the heat radiating portion and the varistor element body. Consequently, in the varistor, cracks hardly occur between the varistor portion and the heat radiating portion during firing (or during binder removal), thereby, ensuring sufficient bonding strength between the varistor portion and the heat radiating portion. Therefore, heat conducted to the varistor portion is radiated efficiently conducting through electrically conducted paths formed in the heat radiating portion from the surface facing the varistor element body to other three surfaces of the heat radiating portion.

Varistor and light emitting device

A varistor comprises an element body, two external electrodes, and a metal conductor. The element body includes a portion having first and second faces opposing each other. Two external electrodes are arranged on the first face of the element body. The metal conductor is arranged on the second face of the element body. The metal conductor has a thermal conductivity higher than that of the element body. At least a region between the two external electrodes and metal conductor in the element body exhibits a nonlinear current-voltage characteristic. The heat transmitted to the varistor is efficiently diffused from the metal conductor in the varistor.

Varistor and light-emitting apparatus

A varistor is provided with a varistor element, and an external electrode disposed on the varistor element. The varistor element contains ZnO as a principal ingredient and contains a rare-earth element and Ca. The external electrode is formed by baking on an outer surface of the varistor element and contains Pt. When the external electrode is formed by baking on the varistor element, a compound of the rare-earth element and Pt and a compound of Ca and Pt are formed near an interface between the varistor element and the external electrode, and exist there. The existence of these compounds enhances the bonding strength between the varistor element and the external electrode.

Varistor and method of producing varistor

A varistor comprises a varistor portion, a metal portion, and buffer portion. The varistor portion has a varistor element body exhibiting a nonlinear current-voltage characteristic and two electrode portions. The metal portion has a thermal conductivity higher than that of the varistor element body. The buffer portion is disposed between the varistor portion and metal portion so as to be bonded to each of the varistor portion and metal portion and mainly composed of glass. The two electrode portions are arranged in the varistor element body so as to be electrically insulated from each other while exposing at least a portion of each thereof from an outer surface of the varistor element body. The metal portion and varistor portion are joined firmly to each other. The heat transmitted to the varistor can efficiently be diffused from the metal portion.

A varistor has a varistor element body, and an external electrode disposed on the varistor element body. The varistor element body contains ZnO as a principal component, and a rare-earth metal. The external electrode has an electrode layer. The electrode layer is formed on an external surface of the varistor element body by simultaneous firing with the varistor element body. The electrode layer contains Pd.

Varistor and method of producing the same

A laminated chip varistor comprises a varistor body, first and second inner electrodes, a heat conductor, and first and second outer electrodes. The varistor body has first and second outer faces. The first and second inner electrodes are disposed in the varistor body so that at least portions thereof are opposing to each other. The first and second outer electrodes are formed on the first outer face, the first outer electrode being connected to the first inner electrode, and the second outer electrode being connected to the second inner electrode. The heat conductor is formed in the varistor body extending in a direction from the first outer face toward the second outer face with one end face thereof exposed on the first outer face and the other end face thereof exposed on the second outer face.

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Tokyo, Japan

Yo Saito