基于VO_2/TiO_2/FTO微结构的电压诱导相变存储器特性  

Characteristics of the Phase Change Memory Induced to Electric Field Based on the VO_2/TiO_2/FTO Microstructure

作　　者：陈培祖 李毅[1,2] 蒋蔚[1] 徐婷婷[1] 伍征义 张娇[1] 刘志敏[1] 

机构地区：[1]上海理工大学光电信息与计算机工程学院,上海200093 [2]上海市现代光学系统重点实验室,上海200093

出　　处：《半导体技术》2017年第5期387-393,共7页Semiconductor Technology

基　　金：国家高技术研究发展计划(863计划)资助项目(2006AA03Z348);教育部科学技术研究重点项目(207033);上海市科学技术委员会科技攻关计划资助项目(06DZ11415);上海市教育委员会科技创新重点项目(10ZZ94);上海领军人才培养计划资助项目(2011-026)

摘　　要：相变存储器作为下一代具有竞争力的新型存储器,其基础和核心是相变存储介质。为了制备基于VO_2薄膜的非易失性相变存储器,首先采用等离子体增强化学气相沉积法在氟掺杂二氧化锡(FTO)导电玻璃衬底上沉积一层厚度为100 nm的TiO_2薄膜,再通过直流磁控溅射法制备VO_2薄膜,并在TiO_2/FTO复合薄膜上形成VO_2/TiO_2/FTO微结构,用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、四探针测试仪和半导体参数测试仪表征分析微结构的结晶和非易失性相变存储特性。结果表明,N_2和O_2的体积流量比为60∶40时,在TiO_2/FTO上可生长出晶向为<110>的高质量VO_2薄膜,在VO_2/TiO_2/FTO微结构两侧反复施加不同的脉冲电压,可观测到微结构具有非易失性相变存储特性,在67,68和69℃温度下的相变阈值电压分别为8.5,6.5和5.5 V,相比多层膜结构的相变阈值电压降低了约37%。The phase change storage medium is the basis and core of the phase change memory, which is regarded as a competitive novel memory for the next generation. In order to fabricate the non- volatile phase change memory based on the VO2 thin film, a TiO2 thin film with a thickness of 100 nm was deposited on the fluorine-doped tin oxide （FTO） conductive glass substrate by the plasma enhanced chemical vapor deposition firstly. Then the VO2 thin film was prepared by the DC magnetron sputtering method, and VO2/TiO2/FTO microstructures were fabricated on TiO2/FTO composite films. The microstructure crystallization and the characteristic of non-volatile phase change memory were characterized and analyzed by the X-ray diffraction （XRD）, scanning electron microscope （ SEM）, four probes tester and semiconductor parameter tester. The results show that high-quality VO2 thin films can be deposited on the TiO2/FTO along the crystal orientation of 〈 110〉 at 60 ： 40 volume flow ratio of N2 and O2. The characteristics of the non-volatile memory were observed when the different pulse voltages were applied to both sides of the VO2/TiO2/FTO microstructure repeatedly. The phase change threshold voltages are 8.5, 6.5 and 5.5 V when the ambient temperatures are 67, 68 and 69 ℃ respectively, which is about 37% lower than that of the multilayer film structure.

关 键 词：VO2/TiO2/FTO 直流磁控溅射 相变存储器 阈值电压 电致相变 

分 类 号：O484.4[理学—固体物理] TN303[理学—物理]