Correlation Between Resistance State and Saturation Magnetization in (In, Co)-Codoped ZnO Thin Film

The special material property in ZnO-based thin film was investigated in this study. The indium and cobalt codoped ZnO thin film was deposited by using a magnetron cosputtering method. Bipolar resistive switching behavior and room temperature ferromagnetism have been observed in (In, Co)-codoped ZnO thin film. In particular, we measured M-H curves of the (In, Co)-codoped ZnO thin film with the bipolar resistive switching behavior in initial state, high resistance state and low resistance state. The saturation magnetization of the (In, Co)-codoped ZnO thin film with the bipolar resistive switching behavior in low resistance state was larger than that of high resistance state. In addition, much evidence has shown that the resistive switching effect and ferromagnetic property could be attributed to the intrinsic defects [1]- [3]. As evidenced from the photoluminescence and x-ray photoelectron spectra results indicate that there is oxygen vacancy in the (In, Co)-codoped ZnO thin film. The results clearly demonstrate the oxygen vacancy is crucial for the entire class of the ferromagnetism and bipolar resistive switching effect in (In, Co)-codoped ZnO thin film. Interestingly, the (In, Co)-codoped ZnO thin film not only shows stable bipolar resistive switching behavior, but also exhibits room temperature ferromagnetism in all of the resistance states for potential spintronic device applications in the future.