Resistive Switching Properties through Iodine Migrations of a Hybrid Perovskite Insulating Layer

This study reports a low‐temperature processable, resistive switching (RS) device based on an inorganic–organic hybrid perovskite, i.e., methylammonium lead iodide (CH3NH3PbI3 or MAPbI3) via a fast deposition–crystallization method, as the multifunctional insulator layer to form metal/insulator/metal structure in which Al and p+‐Si wafer are used as the top and the bottom metal electrodes, respectively. The MAPbI3‐RS device shows acceptable RS characteristics with a switching window of 103 at a low voltage region (≈5 V), a stable endurance during 200 cycles, and a high retention for a prolonged time at 104 s. The operation mechanism of the MAPbI3‐RS device is based on ion (simultaneously vacancy) migration, especially iodine ions, which is analogous to that of oxygen ions in the conventional oxide‐based RS devices, confirmed through X‐ray photoelectron spectroscopy and energy‐dispersive X‐ray spectroscopy measurements. Furthermore, unusual multiresistance states are achieved from the MAPbI3‐RS device under light illumination due to the photosensitivity of MAPbI3. A resistive switching (RS) device is fabricated with an insulation layer based on inorganic–organic perovskite, as well as the operation mechanism of a methylammonium lead iodine (MAPbI3)‐based RS device is verified. The MAPbI3‐RS device exhibits acceptable resistive switching property, including a switching window at low voltage regions, stable endurance, and a high retention.