Modulation of Resistive Switching Behaviour of TaOx-based Memristor Through Device Engineering

Abstract

Tantalum oxide (TaO<inf>x</inf>)-based memristor has been emerged as a promising candidate for non-volatile memory and neuromorphic computing system as it offers low-power and high-speed operations with possibility of high-density integration in 3-D crossbar array. Although many studies have reported bipolar resistive switching behavior, a critical understanding of the factor affecting the switching behavior is still missing. Therefore, in this work, we examine the impact of device design parameters, such as activation energy of conduction, filament radius, and oxide thickness, on the resistive switching behavior and its implication on non-volatile crossbar memory. The device performance investigation is done using fully calibrated numerical simulation model, based on self-consistent solutions of current continuity, heat transport and continuity equations for accurately capturing field and temperature-assist migration of oxygen vacancy. The results shows that a lower values of filament radius and activation energy are right choices for achieving a lower sneak current and hence improve the readout margin for crossbar array; however, the optimum selection of filament radius is important as it reduces switching current and increases the read voltage. We also investigate the scaling behavior of the resistive layer thickness.