Effect of Mn addition on dc-electrical degradation of multilayer ceramic capacitor with Ni internal electrode

The effect of Mn addition on the microstructure and electrical properties, especially on the dc-electrical degradation, of the X7R-type multilayer ceramic capacitor with Ni internal electrode (Ni-MLCC) with thin active layers was investigated. As the amount of Mn increased, grain growth was suppressed, and the temperature characteristic (TC) curve was flattened. I-V characteristic measurements revealed that nonlinearity coefficient (alpha) at a high electric field of more than 10 VIAM was decreased, and the lifetime during the highly accelerated lifetime testing (HALT) under 20 V//mum was improved, as the Mn content increased. It was found that Mn addition caused the change of the electrical properties of the grain boundary (GB). The effect of Mn on dc-electrical degradation during HALT was investigated by introducing impedance measurement at elevated temperatures from the microstructural view point. The roles of Mn on dc-electrical degradation during HALT were proposed.