An investigation on DC conduction in ceramic capacitors

Long term leakage currents in BaTiO₃ based multilayer ceramic capacitors (MLCs) with and without polarity reversal at room temperature and 225°C were measured, and comparison was made between these conduction results. It is shown that charges are injected and accumulated near the electrode/dielectric interface of MLC at room temperature, while ions are transported and accumulated near the cathode at elevated temperature. Also, the DC conduction current can be dominated by different conduction processes due to the change of migration ion density in bulk which changes with temperature. It is considered that the relationship between the space charge accumulation and conduction process discussed here will be useful to study the electrical properties of dielectric materials