Mechanism of improvement of resistance degradation in Y-doped BaTiO3 basedMLCCs with Ni electrodes under highly accelerated life testing

The mechanism of improvement of resistance degradation irt Y-doped BaTiO3 b ased multilayer ceramic capacitors (MLCCs) with Ni electrodes has been stud ied using electrical measurement techniques, minor phase identification and rite measurement of oxygen vacancy concentration. Admittance spectroscopy and thermally stimulated current measurements show the relaxation due to ba rium vacancy states caused by Y doping. The minor phase identification by X RD indicated those Y3+ substitutes for perovskite A-site. Oxygen vacancy co ncentration measurement indicated that Y decreases the oxygen ion vacancy c oncentration in BaTiO3. These results suggest that Y3+ acts as a donor and creates barium vacancies, which compensate for the oxygen vacancies and the reby improve the resistance degradation. (C) 1999 Published by Elsevier Sci ence Limited. All rights reserved.