掺钨VO_2薄膜的电致相变特性  

Characteristics of electrically-induced phase transition in tungsten-doped vanadium dioxide film

作　　者：张娇[1] 李毅[1,2] 刘志敏[1] 李政鹏 黄雅琴 裴江恒 方宝英[1] 王晓华[1,3] 肖寒 

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 [3]上海电力学院电子与信息工程学院,上海200090 [4]上海健康医学院影像学院,上海201318

出　　处：《物理学报》2017年第23期277-285,共9页Acta Physica Sinica

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

摘　　要：采用直流磁控溅射与后退火工艺相结合的方法,在掺氟SnO_2(FTO)导电玻璃基底上制备了高质量的掺钨VO_2薄膜,对薄膜的结构、表面形貌和光电特性进行测试,分析了钨掺杂对其相变性能的影响.结果表明,室温下掺钨VO_2薄膜的阈值电压为4.2 V,观察到阈值电压下约有两个数量级的电流突变.随着温度升高,相变的阈值电压降低,且电流突变幅度减小.当施加8 V电压时,分别在不同温度下测试了掺钨VO_2薄膜的透过率.温度为20和50℃时,掺钨VO_2薄膜相变前后的红外透过率差量分别为23%和27%.与未掺杂的VO_2薄膜相比,掺钨VO_2薄膜具有相变温度低、阈值电压低和电阻率小的特点,在高速光电器件中有广阔的应用前景.The phase transition characteristics of tungsten-doped vanadium dioxide film driven by an applied voltage are studied in the paper.A high-quality film is successfully deposited on an FTO （F：SnO2） transparent conductive glass substrate by direct current magnetron sputtering and post-anneal processing.First of all,an FTO substrate is placed in the chamber of magnetron sputtering system after being cleaned and dried.Then W-doped vanadium film is fabricated on the substrate with V-W alloy target with 1.4% W by mass fraction.In the process of magnetron sputtering,the operating pressure is kept at 3.0×10-1 Pa,and the operating voltage and current are 400 V and 2 A,respectively.Finally,W-doped VO2 film with a thickness of about 310 nm is prepared by being annealed at 400℃ in air atmosphere for 2.5 h.In order to explore the crystal structure,element constituents,surface morphology,roughness and photoelectric properties of W-doped vanadium dioxide film,it is respectively characterized by X-ray photoelectron spectroscopy （XPS）,X-ray diffraction （XRD）,scanning electron microscope （SEM）,atomic force microscope （AFM） and semiconductor parameter analyzer.The XPS analysis confirms that there are no other elements except vanadium,oxygen,carbon and tungsten on the surface of W-doped VO2 film.The XRD patterns illustrate that tungsten-doping exerts an influence on the crystal lattice of VO2,but the film still prefers the orientation （110）.The SEM and AFM images display that the film with low roughness has a compact structure and irregular crystal particles.Tungsten-doping is found to be able to improve the surface morphology of VO2 thin film significantly.In addition,a remarkable change in electrical resistivity and a narrow thermal hysteresis loop are also obtained in the metal-semiconductor phase transition.Further,the influences of tungsten-doping on the phase transition properties of the film are analyzed.The experiment demonstrates that the threshold voltage at which the phase transition of W-doped

关 键 词：掺钨VO2薄膜 电致相变 阈值电压 光透过率 

分 类 号：O484[理学—固体物理]