Multiscale Simulation of ReRAMs Based on the Valence Change mechanism

Redox-based resistive switching devices based on the valence change mechanism can be switched between different resistance states by applying appropriate voltage stimuli. They consists of a simple metal/insulator/metal structure and could be applied in future non-volatile memories or neuromorphic circuits. In this work simulation models for these devices are presented ranging from the atomistic scale to circuit level abstractions. Atomistic models using density functional theory and the non-equilibrium Green's function formalism are applied to understand the conduction process in Pt/SrTi
_O3
/Nb:SrTi
_O3
VCM devices. The results of the atomistic simulations are consistent with the simulation results using a continuum model based on single-band transport theory. The continuum model is further used to simulate switching dynamics of VCM devices, showing that the metal/insulator interfaces have a strong impact on the switching behavior. Finally, a compact model is presented that reduces the complexity of the lower level models.