Matsushita Electric Industrial Co., Ltd.

Kimio Kobayashi

Yasuo Wakahata

Iwao Ueno

Akihiro Takami

Kaori Okamoto

Kaori Shiraishi

Youichi Ogoshi

A method for manufacturing semiconductor-type laminated ceramic capacitors with a grain boundary-insulated structure including the steps of calcinating starting material of mixed powder in air or in nitrogen atmosphere after grinding, mixing and drying the mixed powder; forming raw sheets; printing a pattern of inner electrode paste on the surface of the raw sheets; calcinating the laminated body in air; sintering the laminated raw sheets in reducing atmosphere or in nitrogen atmosphere after calcination; re-oxidizing in air after sintering; and covering the edges of sintered ceramic sheets with outer electrode paste and baking after re-oxidation, terminals of inner electrodes being exposed to the edges, wherein: the starting material of mixed powder comprises a material of the composition Sr.sub.(1-x) Ba.sub.x TiO.sub.3 containing excess Ti to make a final molecular ratio of Ti to Sr.sub.(1-x) Ba.sub.x in the range of 0.95.ltoreq. Sr.sub.(1-x)Ba.sub.x /Ti&lt; 1.00 (where x is in the range of 0&lt; x.ltoreq. 0.3); a first component of at least one or more kinds of the compounds selected from Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, V.sub.2 O.sub.5, W.sub.2 O.sub.5, Dy.sub.2 O.sub.5, Nd.sub.2 O.sub.3, Y.sub.2 O.sub.3, La.sub.2 O.sub.3, or CeO.sub.2 ; a second component of Mn and Si converted into MnO.sub.2 and SiO.sub.2 respectively; and an optional third component of at least one or more kinds of the compounds selected from Na.sub.2 SiO.sub.3, NaAlO.sub.2, Li.sub.2 SiO.sub. 3, LiAlO.sub.2, and Al.sub.2 O.sub.3.

Ceramic capacitor with a grain boundary-insulated structure

A laminated semiconductor ceramic capacitor with a grain boundary-insulated structure comprises a semiconductor ceramic block with a grain boundary-insulated structure, a plurality of Ni inner electrodes and outer electrodes, wherein the Ni inner electrodes are obtained from a paste containing a powder prepared by solubilizing at least one compound containing an atom selected from the group consisting of Li, Na and K into Ni or an Ni containing compound; the Ni inner electrodes are placed in a substantially parallel manner within the ceramic block to reach to the corresponding opposite edges of the ceramic block alternatively one by one; and the outer electrodes are electrically connected to the corresponding edges of the inner electrodes, respectively.

Laminated semiconductor ceramic capacitor with a grain

Semiconductor-type laminated ceramic capacitor with a grain

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Hirakata, Japan

Kimio Kobayashi