Effect of internal field on the high resistance state retention of unipolar resistance switching in ferroelectric vanadium doped ZnO

Abstract

We report the effect of an internal field on the high resistance state (HRS) retention of unipolar switching in ferroelectric vanadium (V) doped ZnO thin films. ZnO thin films doped with 1%, 3%, and 5% of V were found to have an increased internal field as the V concentration increased. The effect of an internal field on resistance switching was observed from the lower set voltage and shorter high resistance state retention time. A physical model was applied to explain the relationship between the internal field and the HRS retention, and a good agreement was obtained with the experimental data. Our result suggested that the internal field can reduce the activation energy of the redox process for generating oxygen vacancies, which subsequently affect the formation of conducting filaments in the resistance switching process.