Mechanism of ferroelectric resistive switching in Bi0.9La0.1FeO3 thin films

Resistive switching devices are considered as one of the most promising candidates for the next generation memories and nonvolatile logic applications. In this paper, we report an anomalous resistive switching effect in BiFeO3 based hetero-structures. Different from conventional resistive switching devices made of metal oxides, no forming process is needed to obtain a stable resistive switching effect in the ferroelectric resistive switching devices. Both positive and negative current peaks are observed under forward bias and reverse bias, respectively, suggesting that flexible Schottky-like barriers and conductive channels form at the top and bottom interfaces, which play important roles in the resistive switching of Ag/Bi0.9La0.1FeO3/La0.3Sr0.7MnO3 sandwiched structures. These flexible Schottky-like barriers may come from the migration of charged oxygen vacancies/ions under the electric field of sweeping bias and the redistribution of carriers with ferroelectric switching, while the conductive channel resulted from charged oxygen vacancies/ions. These results demonstrate promising prospects for application of the ferroelectric resistive switching effect at interfaces to nonvolatile memory.