Investigation of the Nature and Mechanism of Resistive Switching in TiO2-x

The spatial redistribution of the charged point defects under direct-current (DC) biasing can have significant implications for electroceramic device performance and lifetime [1,2]. The transport behavior of point defects is regulated by the boundary conditions of the electrodes, which can block ion transfer across the interface to varying degrees. When the electrodes are impermeable to mass transport, there will be an accumulation of point defects in the near-electrode region that can lead to significant modifications in the local electronic carrier concentrations at the interface. Such defect redistribution is responsible for the long-term increases in leakage current in many capacitor devices. On the other hand, this same phenomena can lead to resistive switching behavior via modification of the interface Schottky barrier at the reverse-biased cathode [1-4].