Electrical properties and carrier transport mechanisms of nonvolatile memory devices based on randomly oriented ZnO nanowire networks

Abstract We report reproducible bipolar resistive memory devices based on Au/ZnO nanowire networks (ZnO NWNs)/ITO, which show a high R_on/R_off ratio (∼10⁴) and narrow dispersion of set and reset threshold voltages. The dominant conduction mechanisms of low resistance state and high resistance state were verified by Ohmic behavior and space charge limited current, respectively. The switching mechanism is confirmed in terms of the formation and rupture of conductive filaments, with oxygen vacancies localized on the ZnO NWNs surface involved in. The Au/ZnO NWNs/ITO devices presented in our work show potential applications in the next generation nonvolatile memory field. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)