Evaluation of electrical properties of leaky BiFeO₃ films in high electric field region by high-speed positive-up-negative-down measurement

The electrical properties of leaky ferroelectric BiFeO₃ thin films were evaluated by using a high-speed positive-up-negative-down (PUND) measurement technique. The leakage current density was estimated from the gradient of the pulse response when a constant electric field was applied. The relative permittivity was estimated from an abrupt decrement when the applied field was removed. The twofold remanent polarization without the influence of the leakage current was estimated by subtracting the contribution of a paraelectric component from the abrupt Increment In the pulse response when a positive pulse was applied.