铁酸铋薄膜在小于矫顽电压下的阻变机制

    Resistive Switching Effect of BiFeO 3 Thin Film Under the Voltage Below the Coercive Voltage

    • 摘要: 为了研究利用脉冲激光沉积法制备于SrTiO 3衬底上的Au/BiFeO 3/SrRuO 3结构的阻变效应,实验通过测量样品的 I-V特性曲线来表征样品的阻态变化. 由于BiFeO 3与Au、SrRuO 3功函数的不同在Au/BiFeO 3、BiFeO 3/SrRuO 3两个接触界面形成稳定的肖特基接触,通过改变外部电压控制陷阱能级填充的程度可以改变肖特基势垒高度,从而在施加电压小于矫顽电压时可以形成稳定的高低阻变化,表现出最大可达10 3高低阻电流比的 I-V特性曲线. 对 I-V特性曲线进行不同导电机制的拟合表明:小于矫顽电压下空间电荷限制电流起到了主导作用,陷阱的填充与脱陷是主要的阻变机制.

       

      Abstract: To study the resistive effect of the Au/BiFeO 3/SrRuO 3 fabricated by the pulsed laser deposition on the SrTiO 3 substrate, the resistive effect was characterized by the I-V curves. Due to the different work function between BiFeO 3 and Au, BiFeO 3 and SrRuO 3, the stable Shottky contact was formed between the contact surface of Au/BiFeO 3 and BiFeO 3/SrRuO 3. The Shottky barrier height was changed by application of external voltage to control the filling status of trap levels. Results show that from the I-V curve the film displays the resistive switching behavior under the voltage below the coercive voltage, with the resistance ratio as large as three orders. Through the fitting of I-V curves by different conduction mechanisms, it is confirmed that the conduction of the film is dominated by the space charge limited current (SCLC). The trapping effect was proposed as the resistive switching mechanism for the BiFeO 3 thin film below the coercive voltage.

       

    /

    返回文章
    返回