Modeling the effects of different forming conditions on RRAM conductive filament stability

In order to identify the factors controlling the filament characteristics, we perform physics-based simulations of the inherently stochastic and difficult-to-control forming process using a statistical Monte-Carlo method to model the Hf-O bond-breakage, oxygen ion diffusion and vacancy-oxygen recombination. Simulation results well reproduce the experimental trends observed for the conductivity of the post-forming low resistance state under different forming conditions. It is shown that the distribution of the oxygen ions in the surrounding oxide during forming as well as local filament temperature and electrical field all affect the filament stability.