Photo-induced negative differential resistance in a resistive switching memory device based on BiFeO3/ZnO heterojunctions

Photo-induced novel effect in a material with multiple physical properties has highly important potential applications in the photo-electric multifunctional electronic devices. In this work, the BiFeO3/ZnO bilayer films were sequentially prepared by magnetron sputtering method, which displays an obvious photo-modulated conversion between resistive switching (RS) memory and negative differential resistance (NDR) effect. Through theoretical analysis and simulation calculation, suggesting the NDR effect can be attributed to the inner electric field and the efficiently separated photogenerated electrons and holes under light-irradiation in the interface of the BiFeO3/ZnO p-n heterojunctions, while the RS memory behavior can be attributed to the formation of oxygen vacancies assisted Ag conductive filaments. This work opens up a new way to preparation a multifunction electronic device with photo-modulated conversion between RS memory and NDR effect for potential applications in optical electrical bifunctional devices, electronic information and optical quantum computers, and so on. (C) 2018 The Authors. Published by Elsevier Ltd.