Understanding pulsed-cycling variability and endurance in HfOx RRAM

Resistive switching memory (RRAM) devices based on metal oxides are receiving strong interest for future high-density stand-alone memories and storage class memories. To explore possible applications of RRAM, the set/reset variability and cycling endurance must be addressed and understood. This work shows a comprehensive study of pulsed-operated variability and endurance in HfO_x-RRAM. We analysed the dependence of switching variability on operation current, voltage and pulse-width, providing guidelines to optimize set/reset distributions in oxide RRAM. The impact of pulse-amplitude and pulse-width on cycling endurance is then discussed. The results are explained by a new physics-based model for endurance controlled by defect injection from the bottom electrode during reset.