Cu掺杂的ZnO纳米棒阵列膜的结构与阻变性能

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

摘要:

以Cu掺杂的ZnO(Cu：ZnO,CZO)薄膜(Thin film,TF)为缓冲层、以水热法制备了CZO纳米棒阵列膜(Nanorods film,NRF),研究了CZO NRF的结构与阻变特性。少量Cu₂₊添加可促进纳米棒的结晶及沿c轴取向生长,补偿本征缺陷。所制备的CZO NRF/CZO TF双层器件具有双极性阻变特性,限制电流对其I-V特性和保持特性影响较大,限制电流较小时,器件的开关比会降低。当I_CC分别为10mA和1mA时,开关比的平均值分别为7460和45。与CZO TF单层器件相比,SET电压分布和高低阻值的稳定性均获得明显改善,V_SET分布在+0.3～1.55V之间,HRS≈7.05×10₅～2.1×10₆Ω,LRS≈134Ω。CZO纳米棒为导电细丝的形成提供了大量氧空位,使导电细丝排列整齐、尺寸更均匀,降低了导电细丝形成的随机性。

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.