Large resistive switching and switchable photovoltaic response in ferroelectric doped BiFeO3-based thin films by chemical solution deposition

Abstract

The destructive readout signal distinguishing the ferroelectric polarization state in a memory device has long been seen as the bottleneck for its commercial application. Both ferroelectric resistive switching and the switchable photovoltaic effect provide multiple choices for non-destructive readout. The polycrystalline ferroelectric BiFeO₃-based thin films fabricated by cost-effective chemical solution growth exhibit large resistive switching (with ON/OFF ratios ∼10⁴), which is comparable to switchable diodes and tunnel junctions. Furthermore, switchable photovoltaic response shows stable switching and good retention properties. The standard hysteretic loops of resistive switching current, short circuit current and open circuit voltage versus poling voltage directly indicate hysteretic modulation by ferroelectric polarization, which is the first evidence in polycrystalline BiFeO₃ based films. The present films would be potential candidates for non-destructive ferroelectric memory devices with multiple selections.