Electrochemical Boundary Conditions for Resistance Degradation of Doped Alkaline‐Earth Titanates

In order to improve the understanding of de‐field‐induced resistance degradation, ceramic capacitors made from perovskite‐type titanates are formally treated as solidelectrolyte cells. Based on the consideration of the interfaces in these cells, the degradation process can be unambiguously deduced from the well‐known defect structure and transport properties of the titanates. Additional information is obtained from in situ impedance analyses and transport calculations as well as from comparisons between the degradation rate in single crystals and ceramics of different grain size. Key words: capacitors, titanates, grain boundaries, dielectrics, electrical conductivity.