Hitachi Metals, Ltd.

Toshiki Kida

Kentaro Ino

Hiroyuki Ito

Takeshi Shimada

Naoki Matsushima

Shohei Hata

Atsushi Kazama

Takanori Aono

Ryoji Okada

Eiji Sakamoto

Naoyuki Okamoto

Takesha Shimada

To provide a zinc oxide-based varistor that exhibits adequate characteristics without using antimony. Disclosed is a sintered body for a varistor, including zinc oxide as a main component; 0.6 to 3.0 mol % of bismuth oxide in terms of bismuth (Bi); 0.2 to 1.4 mol % of cobalt oxide in terms of cobalt (Co); 0.1 to 1.5 mol % of chrome oxide in terms of chrome (Cr); and 0.1 to 1.5 mol % of manganese oxide in terms of manganese (Mn), wherein the contents of antimony (Sb), a rare earth element and tin (Sn) are not more than a level of impurities.

Sintered body for varistor, multilayer substrate using same, and production method for these

To improve jump characteristic of BaTiO&#x2014;(BiNa)TiOmaterial. There is provided a process for producing a semiconductive porcelain composition in which a part of Ba is substituted with Bi&#x2014;Na, the process including a step of preparing a (BaQ)TiOcalcined powder (in which Q is a semiconductor dopant), a step of preparing a (BiNa)TiOcalcined powder, a step of mixing the (BaQ)TiOcalcined powder and the (BiNa)TiOcalcined powder, a step of molding and sintering the mixed calcined powder, and a step of heat-treating the obtained sintered body at 600&#xb0; C. or lower; and a PCT heater employing the element prepared by the above steps.

Process for producing semiconductive porcelain composition and heater employing semiconductive porcelain composition

An object is to provide a PTC element that can be made thinner, using a Pb-free semiconductor ceramic composition. The object is achieved with a PTC element including at least two metal electrodes and a BaTiOsystem semiconductor ceramic composition arranged between the electrodes, in which, in the semiconductor ceramic composition, a portion of Ba in the BaTiOsystem is substituted by Bi&#x2014;Na and a semiconductorizing element, vacancies are formed on Bi sites by depleting at least a portion of Bi, and oxygen defects are formed on a crystal thereof. Since the PTCR characteristic at the inside of the semiconductor ceramic composition is negligibly weak in comparison with the PTCR characteristic at the interface between the semiconductor ceramic composition and the electrodes, the PTC element can be made thinner.

PTC element and heating-element module

A packaging structure for hermetically sealing a functional device by solder connection at a wafer level in which a first Si substrate having a concave portion metallized on its internal surface and a second Si substrate metallized at a position opposed to said concave portion are used, the metallization applied to the internal surface of the concave portion of the first Si substrate and the metallization applied to the second Si substrate at the position opposed to the concave portion are connected by molten solder to hermetically seal the functional device between the first Si substrate and the second Si substrate, whereby the wettability of the solder for the two Si substrates is improved, the bondability between the Si substrates is enhanced, and the yield at which the package is manufactured is improved.

Functional device package with metallization arrangement for improved bondability of two substrates

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Tottori, Japan

Toshiki Kida