Asymmetric resistive switching by anion out-diffusion mechanism in transparent Al/ZnO/ITO heterostructure for memristor applications

In this report, the monovalent cations of sodium and potassium are doped into the ZnO matrix to explore for resistive switching . The structural analysis confirms that Na + and K + cations are incorporated into the interstitial sites of ZnO lattice. The Na + and K + doped ZnO thin films (NZO and KZO) have exhibited improved transparency slightly higher than 80 % for the wavelength range 400-1000 nm. Hall and impedance measurements confirms that resistance of the thin films increased after incorporation of Na + and K + cations into the ZnO lattice. The fabricated NZO and KZO thin films-based memory devices exhibited bipolar resistive switching phenomenon with excellent ON/OFF ratio of 10 4 , endurance of ∼ 100 cycles, and charge retention of 10 4 s in both the resistive states. These results imply that NZO and KZO films to have enormous potential to serve as an efficient resistive switching device.