二氧化钒薄膜在α-Al2O3衬底上的外延生长及其金属-半导体相变特性研究

利用ＸＲＤ及ＸＲＤ极图技术表征了用激光剥离技术生长的ＶＯ_２薄膜．结果表明：在衬底温度为５００℃，氧气偏压６．６７Ｐａ的条件下，在Ａｌ_２Ｏ_３（１１２０）衬底上能实现ＶＯ_２的二维外延生长．薄膜的结构除了与沉积工艺有关外，还和衬底的取向密切相关．在Ａｌ_２Ｏ_３（１１２０）衬底上，定向生长的（１００）ＶＯ_２在Ｍｉｌｌａｒ指数＜５时，除了［０１０］以外，不存在其他晶格矢量与衬底相匹配，从而不可能实现三维单晶薄膜的外延生长．电学特性的测试结果显示，在温度为６５℃左右，ＶＯ_２薄膜出现相交，薄膜的电阻率变化达４个数量级．

Epitaxial Growth and Phase Transition Properties of Vanadium Dioxide Thin Film on Sapphire Substrate

Vanadium Dioxide(VO2) thin films deposited on(1120) sapphire substrates by pulsed laser ablation were characterized by using the techniques of XRD , XRD pole figure, RBS/channeling andelectrical measurements The results show that VO2 thin film on the (1120) sapphire grows pi-taxially with out of -plane:(100)VO2/ /(1120)sapphire and in-plane:VO2010]/ /sapphire0001].Channeling cannot be found in RBS/Channeling analysis ,indicating that the film fails to singlecrystalline growth .The further analysis of the crystallography of the (100)VO2 reveals that within 5 lattice periods,no other lattice vector exists in the (100)plane of Vo2 to match the latticeof sapphire,therefore,it is impossible to deposit single crystal thin film on (1120)sapphireas observed in the study .During the phase transition,the electrical resistivity changes aboutfour orders.