Resistive switching performance of fibrous crosspoint memories based on an organic–inorganic halide perovskite

Abstract

The fiber-shaped resistive random access memory (RRAM) is an important subject for flexible wearable electronic textiles. The investigation of the resistive switching (RS) performance of the materials in the basic storage unit (crosspoint) of a flexible fibrous crossbar is very significant for realizing flexible wearable memories. In this work, fibrous crosspoint RRAM devices, abbreviated as FCPe-RRAMs, have been fabricated on the basis of organic–inorganic halide perovskite MAPbI₃. Herein, a functional Al@MAPbI₃ fiber is first prepared via a simple dip-coating method, in which the low-temperature solution processing method and cheap raw materials are conducive to the future large-scale and low-cost production. By optimizing the preparation conditions for MAPbI₃, a pinhole-free, compact and uniform perovskite film is deposited on the bare Al fiber. Then, the FCPe-RRAM devices with a configuration of Al@MAPbI₃/Al are assembled on a homemade holder by perpendicularly crossing the bare Al fiber and the functional Al@MAPbI₃ fiber at a certain bending angle. The FCPe-RRAM devices exhibit a bipolar RS behaviour. The highest ON/OFF ratio reaches up to approximately 10⁶ in the FCPe-RRAM devices, together with a low SET/RESET voltage (+1.66 V/−0.47 V) and a long retention time (>10⁴ s). The FCPe-RRAM devices also exhibit excellent reproducibility and operational uniformity, which are important for practical applications in mass production. The investigation of the RS mechanism suggested that the FCPe-RRAM devices follow the mechanism of conductive metallic filament formation by the generated electrons with the help of thermionic emission. This work reveals the potential promising applications of FCPe-RRAM devices in flexible wearable memories with high storage density.