Temperature-stable dielectric ceramic composition for multilayer ceramic capacitors with base-metal electrodes

摘要

The present invention relates to a temperature-stable dielectric ceramic composition for multilayer ceramic capacitors. The said dielectric composition comprises barium titanate and additives, wherein the barium titanate ranges from 94 to 99 mol % of the said composition, and the additives range from 1 to 6 mol % of the said composition. The additives comprise oxides of Mg, Ca, Ba, Si and Mn, and oxides of one or more elements selected from the group consisting of Co, Sr, Ti and Fe, and an oxide of Re, or carbonates, hydroxide, oxalates, acetates or nitrates of the above elements. Re represents one or more elements selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb and Lu. After being sintered at 1200° C. to 1350° C. under reducing atmosphere, the room-temperature dielectric constant of the composition is 2000 to 3500 and its temperature coefficient of capacitance satisfies X7R characteristic (EIA standards). The composition is useful as material for multilayer ceramic capacitor with ultra-thin dielectric layer (thickness less than 10 &mgr;m).