Flexible, Temperature-Resistant, and Fatigue-Free Ferroelectric Memory Based on Bi(Fe0.93Mn0.05Ti0.02)O3 Thin Film

ACS Appl Mater Interfaces. 2019 Apr 3;11(13):12647-12655. doi: 10.1021/acsami.9b01464. Epub 2019 Mar 25.

Abstract

A recent hot-spot topic for flexible and wearable devices involves high-performance nonvolatile ferroelectric memories operating under compressive or tensile mechanical deformations. This work presents the direct fabrication of a flexible (Mn,Ti)-codoped multiferroic BiFeO3 film capacitor with Pt bottom and Au top electrodes on mica substrate. The fabricated polycrystalline Bi(Fe0.93Mn0.05Ti0.02)O3 film on mica exhibits superior ferroelectric switching behavior with robust saturated polarization ( Ps ∼ 93 μC/cm2) and remanent polarization ( Pr ∼ 66 μC/cm2) and excellent frequency stability (1-50 kHz) and temperature resistance (25-200 °C), as well as reliable long-lifetime operation. More saliently, it can be safely bent to a small radius of curvature, as low as 2 mm, or go through repeated compressive/tensile mechanical flexing for 103 bending times at 4 mm radius without any obvious deterioration in polarization, retention time at 105 s, or fatigue resistance after 109 switching cycles. These findings demonstrate a novel route to designing flexible BiFeO3-based ferroelectric memories for information storage and data processing, with promising applications in next-generation smart electronics.

Keywords: BiFeO3 film; fatigue-free; ferroelectric memory; flexible; temperature-stable.