Optimization of Conductive Filament of Oxide-Based Resistive-Switching Random Access Memory for Low Operation Current by Stochastic Simulation

Abstract

Large switching current is a great challenge for scaling down of the oxide-based resistive random access memory devices to realize high density and low power memory array. In this paper, large operation current caused by the current overshoot effect during forming process is investigated using a stochastic simulator based on the percolation theory. The electrical characteristic of forming process is simulated and compared with the experimental data. Our simulation demonstrates that the current overshoot effect results in a stronger conductive filament during forming process, which will cause a larger operation current in subsequent switching cycle. Furthermore, our simulation results reveal that low sweeping rate, high ambient temperature, high doping concentration and high pre-exist oxygen vacancies (VO) concentration are beneficial to the control of conductive filament evolution and the suppression of the current overshoot effect, which is critical for low reset current and low operation power resistive-switching random access memory (RRAM).