TEMPERATURE-STABLE LEAD-RELAXOR-BASED CERAMIC DIELECTRICS WITH CHEMICAL INHOMOGENEITY

Matrix grains of Pb-relaxor ceramics with chemical inhomogeneity, showing the so-called core-shell structure already reported for BaTiO3-based X7R ceramics, were obtained by a controlled sintering process in a MgO-excess and PbO-excess PMN-PMW-PT system. Multilayer ceramic capacitors exhibiting the X7T specifications were then fabricated from the 8 mol% MgO excess and 4 mol% PbO excess powder. Their chemical inhomogeneity was stable, showing a decrease of capacitance of only 2.9% after an 800-h aging test.