Studies on resistive switching times in NiO thin films grown by pulsed laser deposition

Abstract

The resistive switching dynamics of NiO thin films in Au/NiO/Pt device configuration have been investigated to measure the switching times of set and reset events and their dependence on compliance current and switching voltages. The set switching time was found to be ~10 ns at the set voltage of ~1.8 V, while reset switching time was much longer ~150 µs at reset voltage of 0.8 V. With increasing compliance current from 5 to 75 mA during set process, although the resistance contrast of two states improved due to the decrease in the resistance of the low resistance state, the reset switching time increased substantially up to ~3 ms while set time remained nearly unchanged. The fast reset switching time of ~27 ns, comparable to that of set switching time, was achieved by applying a higher reset voltage of ~1.2 V. The observed dependence of reset time on compliance current and reset voltage in NiO thin films was explained in light of the conducting filamentary model in which reset process is of thermal nature and involves dissolution of conducting filaments as a consequence of Joule heating generated by the reset current.