Resistive Switching and Current Conduction Mechanisms in Amorphous LaLuO3 Thin Films Grown by Pulsed Laser Deposition

The unipolar resistive switching characteristics of the amorphous LaLuO₃ thin films deposited by pulsed laser deposition have been studied. Reliable and repeatable nonvolatile switching of the resistance of LaLuO₃ films was obtained between two well defined states of low and high resistance with nearly constant resistance ratio ～10⁷ and non-overlapping switching voltages in the range of 0.66-0.83 V and 1.9-2.7 V respectively. The temperature dependent measurement revealed metallic and semiconducting behavior in low and high resistance states respectively. The switching between low and high resistance states was attributed to the change in the separation between oxygen vacancies in light of the correlated barrier hopping theory. The current conduction mechanism of the device in high-resistance state followed the Poole's law, whereas the conduction in low-resistance state was found to be dominated by percolation. The resistance of low and high resistance states of the film showed no obvious degradation for up to ～10⁴ seconds indicating good retention. The achieved characteristics of the resistive switching in LaLuO₃ thin films seem to be promising for futuristic nonvolatile memory applications.