【作者】 商朗；

【导师】 陈长虹；

【作者基本信息】 华中科技大学 ， 物理电子学， 2008， 硕士

【摘要】 二氧化钒是一种具有热致相变特性的金属氧化物,随着温度的变化,大约在68℃附近,发生从低温半导体相到高温金属相的可逆相变。由于相变温度接近室温,且相变前后材料的光、电性能变化幅度较大,VO2在许多领域都有重要的应用价值。另外,VO2为纯电子型Mott-Hubbard相变材料,可以采用电子注入的方式来触发材料发生相似的相变效果,所以通过外加电场来场效应控制材料物理特性发生变化可以实现电光开关功能。本文重点研究了采用直流磁控溅射法制备VO2薄膜的工艺方法,在硅衬底上制备了多种不同工艺条件下的钒氧化物薄膜。通过X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)、扫描电子显微镜(SEM)、Raman散射光谱仪、傅立叶变换红外光谱仪(FTIR)、NKD薄膜分析仪等薄膜分析测试工具手段对这些样品成分、结构、表面形貌、光学特性等方面进行测试和分析,得出了钒氧化物薄膜制备工艺中的氧氩比和衬底温度等参量与薄膜性质的关系,得到了制备VO2薄膜的最佳工艺条件。通过光刻和刻蚀工艺在制作了基于VO2薄膜的电光开关器件,在外加电场控制下,用Raman光谱仪测试了器件的相变特性,用FTIR测试了器件的开关性能特性。发现在外加电压大小达到4V以上时可以使VO2薄膜发生相变,且器件的反射率急剧增大,实现了开关功能。更多还原

【Abstract】 Vanadium dioxide is a kind of metallic compound which undergoes a reversible semiconductor-metal phase transition near 68℃. The phase transition is accompanied by significant changes in optical and electrical properties. For the characteristics that its phase transition temperature is near to room temperature and its optical electrical performance have changed much during phase transition, VO2 has a great deal of potential applications. In addition, VO2 is a purely electronic Mott–Hubbard transition material, which phase transition can be similarly induced by adding more electron. So we can use electric field to change the phase estate of the material. In the same time, the physics state of the material is changed and the electro-optic switch purpose is achieved.In the thesis, VO2 thin films are deposited on the silicon substrate by magnetron sputtering by different technics conditions. The composition, microstructure, surface shape and optics properties of VO2 thin films are studied with XRD, XPS, SEM, Raman dispersion spectrum apparatus. The best technics condition to produce VO2 thin film is found out.VO2 thin film based electric-optical switching is made by lithography and etching process. Under the control of electric fields, the phase transition character of the device is tested by Raman dispersion spectrum apparatus, and the switching character is tested by FTIR. It is found out that above 4V, phase transition appears in VO2 thin film, and the reflectance of the device increases sharply. The switching ability is fulfilled.更多还原