中文摘要：

采用磁控溅射方法沉积TiO2薄膜及电极层，制备W／TiO2／ITO薄膜阻变存储器单元。利用原子力显微镜、X射线衍射仪、X射线光电子能谱仪对薄膜进行表征，测试结果表明：TiO2薄膜表面平整、致密；组织结构以非晶为主，仅有少量的金红石相TiO2（110）面结晶；钛氧比为1：1．92，其内部存在少量的氧空位。在电学测试中，元件呈现出了稳定的双极阻变现象，KSet分布在0．92V左右，VResent分布在-0．82V左右；元件窗口值稳定，数据保持特性良好。通过对元件I-V曲线线性拟合结果的分析，我们认为元件的阻变机理由导电细丝机制主导。进一步的分析发现，该导电细丝是由钨原子构成，钨原子在电场作用下发生氧化还原反应并在TiO2薄膜层中迁移，造成了导电细丝的形成和断裂。

英文摘要：

W/TiO2/ITO thin film resistive random access memory, including TiO2 film and electrode layers was prepared by magnetron sputtering method. The film was characterized by atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy. The testing results show that the surface morphology of deposited TiO2 thin film is smooth and dense ; the structure of the film is mainly amorphous phase with a small amount of crystallized rutile （110） planes ; the ratio of titanium and oxygen is 1 ： 1.92 and few oxygen vacancies exist inside the film. The device displays a stable bipolar resistive switching behavior in electrical testing with Vse, around 0.92 V and VR around - 0.82 V. The stable memory window and fine retention performance are also found in electrical testing. By analyzing the linear fitting for I-V curve, it is believed that the resistive switching is governed by conducting filament. Further study showed that the conducting filament is formed by Tungsten atoms, i. e. , the redox reaction and the migration of Tungsten atoms in TiO2 film under a bias cause the formation and rupture of conducting filaments.