Bipolar resistive switching behavior and conduction mechanisms of composite nanostructured TiO2/ZrO2 thin film

Abstract In this work, TiO2/ZrO2 bilayer thin film was prepared on fluorine doped tin oxide (FTO)/glass substrates by using a simple and low-cost chemical solution deposition method. Reproducible bipolar resistive switching (RS) characteristics in Au/TiO2/ZrO2/FTO/glass devices are reported in this work. TiO2/ZrO2 bilayer thin films prepared in this work shows reversible bipolar resistive switching and unidirectional conduction performances under applying voltage and these special performances of TiO2/ZrO2 bilayer thin films was first reported. Obvious resistive switching performance can be observed after setting a compliance current, the ratio of high/low resistance reached about 100 at a read voltage of +0.1V and −0.1V and the RS properties showed no obvious degradation after 100 successive cycles tests. The resistive switching characteristics of Au/TiO2/ZrO2/FTO/glass device can be explained by electron trapping/detrapping related with the vacancy oxygen defects in TiO2/ZrO2 bilayer thin film layer. According to slope fitting, the main conduction mechanisms of the sample are Ohmic and Space charge limited current mechanism.