Structure and resistive switching behaviors of Cu doped ZnO nanorod array films

Abstract:

Cu doped ZnO(CZO)Nanorod films (NRF) are fabricated on CZO thin films (TF) coated FTO substrates by the hydrothermal method, and the microstructure and resistive switching characteristics are further investigated.The doping of Cu₂₊ helps to improve the quality of crystallization and the oriented growth of nanorods along c axis, in the meantime, effectively compensates the intrinsic defects of nanorods. The prepared CZO NRF/CZO TF devices exhibit bipolar resistive switching behaviors. The compliance current has a great effect on I-V curves and retention performance, and the OFF/ON ratio decreases under a low value of I_CC. The mean OFF/ON ratios are 7460 and 45 respectively when I_CC=10mA and 1mA. Compared with the CZO TF devices, CZO NRF/CZO TF devices show narrow distribution of V_SET and good stability of HRS and LRS, with the V_SET of +0.3～1.55V, HRS of 7.05×10₅～2.1×10₆Ω and LRS of ≈134Ω. CZO nanorods provide large quantities of oxygen vacancy for the formation of conductive filaments with orderly arrangement and uniform size.