Evidence for threshold switching in the set process of NiO-based RRAM and physical modeling for set, reset, retention and disturb prediction

This work addresses the set and reset mechanisms in NiO-based resistive-switching memory (RRAM) devices, presenting a new physics-based model for RRAM reliability and programming. We show experimental evidence that the set process is initiated by threshold switching, that is a reversible electronic transition to a high conductance state. We develop set/reset models for prediction of programming voltage and time under sweep or pulsed conditions. The speed limitations of RRAMs are then assessed by a detailed study of reset operation in the pulsed regime, showing evidence for over-reset under high-voltage, fast programming conditions (< 1 mus).