LiNbO3-based ferroelectric tunnel junctions with changeable electroresistance for data storage

Abstract

Ferroelectric tunnel junctions (FTJs) have attracted considerable attention for potential applications in the next-generation data storage technologies. In this work, we have grown high-quality LiNbO₃ single crystal films on STO (111) substrates by rotational epitaxy. The certain ferroelectricity was achieved in nanoscale epitaxial LiNbO₃ films. Then, the Au/LiNbO₃/Nb: SrTiO₃ FTJ was fabricated, and the nonvolatile resistive switching controlled by the nonvolatile polarization switching was observed. The Au/LiNbO₃/Nb: SrTiO₃ FTJs regulate the quantum tunneling effect through ferroelectric polarization reversal to obtain multi-level resistive states, thereby achieving data storage functionality. At room temperature, the ON/OFF current ratio can exceed 10³. Furthermore, the FTJs also exhibit excellent retention for more than 10³ s and good switching endurance for 2000 cycles. The results suggest the application potential of this LiNbO₃-based FTJ for next generation nonvolatile ferroelectric memories.