Bipolar resistive switching with self-rectifying behaviors in p-type AgCr1−xMgxO2 thin films

Abstract

Resistive random access memories with self-rectifying behaviors, in which the sneak-path issue in passive crossbar arrays can be alleviated without additional access devices, have been investigated recently. The applications of p-type transparent oxide semiconductors as a memory medium will pave the way for realizing all-transparent memories and integrating on the complementary metal-oxide-semiconductor devices. Here, Ag-based p-type delafossite AgCr1−xMgxO2 thin films were prepared onto n-Si wafers to investigate the resistive switching (RS) performance. Bipolar RS with self-rectifying behaviors were observed in the Au/AgCr0.92Mg0.08O2/n−Si sandwich structure, showing improved rectification ratio, On/Off ratio, and switching durability. The change of the oxygen vacancy concentration resulting from Mg doping plays a key role in determination of the RS. The intrinsic rectifying behavior in the low resistance state is attributed to the existence of a Schottky-like barrier in the AgCr1−xMgxO2/n−Si p-n heterojunction. The RS behavior originates from the modification of the barrier, which is induced by the trapping/detrapping of charge carriers in oxygen vacancies at the interface. The results will provide novel RS devices based on p-type transparent delafossite thin films with a self-rectifying feature.