Understanding Metal Oxide RRAM Current Overshoot and Reliability Using Kinetic Monte Carlo Simulation

A Kinetic Monte Carlo (KMC) numerical simulator is developed for metal oxide resistive random access memory (RRAM). In this work, substantial improvements are made on the stochastic model in [1] by including multiple conduction mechanisms, local field and local temperature profile, and tracking of the individual oxygen migration path. The improved simulator shows extended capability to study a full set of RRAM characteristics such as set/forming current overshoot, endurance, and retention, etc. The simulations suggest that 1) eliminating the forming process and decreasing the parasitic capacitance is required for minimizing the overshoot effect and reducing the reset power consumption; 2) the degradation of endurance can be explained by oxygen escaping from the electrode during cycling; 3) the oxygen migration barrier can be extracted from the retention baking test over a suitable temperature range.