PLD法制备TiO2薄膜及电阻转变特性研究

采用脉冲激光沉积法（PLD），以Pt(111)/Ti/SiO₂/Si为衬底，制备了具有电阻转变特性的TiO₂薄膜.X射线衍射（XRD）分析未发现明显的TiO₂结晶峰，薄膜呈纳米晶或非晶态.扫描电子显微镜（SEM）及原子力显微镜（AFM）分析表明，TiO₂薄膜表面平整、光滑致密.电学测试结果表明，TiO₂薄膜具有明显的单极性电阻转变特性，高低阻态比值达到10⁴.高阻态下薄膜的导电过程可用空间电荷限制电流模型解释，过程中存在软击穿现象.在此基础上，对薄膜中丝导电通道的产生及熔断过程进行了初步分析.

Study on the Resistive Switching Behaviors of TiO2 Thin Films by Pulsed Laser Deposition

The TiO₂ thin films with resistive switching behaviors were grown on Pt (111)/Ti/SiO₂/Si substrates by pulsed laser deposition (PLD). Scanning electrical microscope (SEM) and atomic force microscope (AFM) were employed to characterize the as-grown films respectively. No evident diffraction peak of TiO₂ is found in X-ray diffraction (XRD) pattern. The films exhibit nanocrystalline or noncrystalline. The results show that the surfaces of the films are flat, smooth and dense. The results of electrical test indicate that TiO₂ thin films show a unipolar resistive switching behavior, and the high-resistance to low-resistance ratio can reach 10⁴. The electrical conduction of the films at high resistance state is controlled by the space charge limited current mechanism, and the soft-set phenomenon is found. The formation and rupture of conducting filaments in TiO₂ thin films are preliminarily analyzed.