A BaTiO3-based flexible ferroelectric capacitor for non-volatile memories

Abstract

BaTiO₃ (BTO) ferroelectric films, which are renowned for their lead-free compositions, superior stability, and absence of a wake-up effect, are promising candidate materials in the field of non-volatile memories. However, the prerequisites for high-temperature conditions in the fabrication of ferroelectric thin films impose constraints on the substrate choice, which has limited the advancement in non-volatile memories based on single-crystal flexible BTO films with robust ferroelectric properties. Herein, a technique has been developed for the fabrication of flexible devices using a pulsed laser deposition system. BTO ferroelectric films have then been deposited onto a flexible mica substrate, with SrTiO₃ (STO) serving as a buffer layer. The obtained flexible BTO devices exhibited excellent ferroelectricity, with a maximum polarization (2P_max) of up to 42.58 μC/cm² and a remnant polarization (2P_r) of up to 21.39 μC/cm². Furthermore, even after 1000 bending cycles, the bipolar switching endurance remained high at 10¹² cycles. After 10⁴ s, the flexible BTO device still maintained excellent polarization characteristics. These results make the flexible BTO ferroelectric thin film a potential candidate for the next generation of non-volatile memories.