【作者】 张涛；

【导师】 赵高凌；

【作者基本信息】 浙江大学 ， 材料学， 2005， 硕士

【摘要】 氮化钛(TiN)是近年来所研究的新型宽带半导体材料中一种性能优异,极具发展潜力和拥有广泛应用前景的硬质合成材料。它具有优异的热稳定性、耐腐蚀性、高机械硬度、宽的光学带隙、低的电阻率和在可见光区及红外光区有优良的光学性能。令人感兴趣的是TiN的低的电阻率和在可见光区及近红外区的优良的光学性能的特点。另一方面,低辐射膜在节能方面有重要意义。本研究在对低辐射膜和TiN薄膜的光、电性能做了全面的文献综述的基础上,提出了用氮化钛薄膜作为低辐射膜应用的设想。希望利用氮化钛薄膜的良好的导电性、其光性能与金、银等贵金属薄膜的很相似:膜较薄时,在可见光区半透明及红外光区的高反射的特点。得到一种新型的节能低辐射镀膜玻璃。同时本论文还全面介绍了节能镀膜玻璃,特别是低辐射镀膜玻璃的发展概况、节能特性、原理、低辐射膜的种类以及常用的制备方法等。本文以无机物TiCl4和NH3为先驱体,以惰性气体N2为载气在玻璃基板上采用常压热分解化学气相沉积法制备得到了TiN薄膜。运用XRD、SEM、TEM、XPS、四探针电阻仪、紫外可见光谱仪等手段对制备的薄膜样品进行了测试和分析。文章系统研究了基板温度、沉积时间、TiCl4浓度、NH3浓度等制备参数对TiN薄膜结构、组成的影响及它们之间的关系。研究结果发现采用常压热分解CVD法制得的TiN薄膜均为氯化钠型结构的多晶薄膜。随着基板温度的提高、沉积时间的延长和反应物浓度的增加,薄膜厚度随之增加,薄膜内部晶粒发育逐渐趋于完整,颗粒长大,晶界减少,能获得结晶性能较好的薄膜。但是薄膜厚度的增大和浓度的提高会恶化膜面的平整度,也会影响薄膜的结晶性能。本论文还对薄膜的光电性能进行了详细的研究。薄膜的导电性能实验表明TiN薄膜的导电机理类似于纯金属导电,其电学性质严格的依赖于显微结构,因而与薄膜的生长条件密切相关。导致TiN薄膜电阻率升高的两个因素,一个是空洞(或孔隙)、另一个是杂质(特别是氧),两者都是有效的散射中心。过量的氧或空洞会引起对电子的杂质散射作用,使得薄膜的导电性能反而降低。薄膜的红外反射性能与薄膜的载流子浓度和迁移率有密切关系,只有提高薄膜的载流子浓度和移率,降低薄膜的方块电阻值,才能大幅提高薄膜的红外反射率。研究得到的薄膜的最佳光电性能:薄膜的方块电阻为34. 5 Ω/(?),可见光透过率为65%,中远红外浙江大学硕士学位论文反射率为60%。 综上所述,在对氮化钦薄膜制备工艺、性能和微结构研究分析的基础上,结合节能镀膜玻璃的应用背景,初步探讨了T州薄膜作为新型低辐射膜的可能性。通过对其光学性能和化学稳定性分析,可以认为在普通玻璃上沉积TIN膜后,能在保持较高的可见光透射率和较低的反射率基础上,提高玻璃的低辐射性能,具有节能效果。关键词CVD、TIN薄膜、红外反射、低辐射镀膜玻璃更多还原

【Abstract】 Titanium nitride （TiN） is an advanced semiconductor material with outstanding physical and chemical properties,such as high thermal conductivity, resistance to corrosion,high mechanical hardness, low electrical resistivity and perfect optical properties in visible and infrared regions. Because of these properties,TiN has been studied extensively. It has already used as a gold substitute for decorative coatings and as a wear-resistant coating on tools. In this thesis,TiN films were studied as a new low emission coating films because of their low electrical resistivity, outstanding optical properties like noble metallic films（Au, Ag）. And for thin TiN films, they were semitransparent in visible region and high reflectance in infrared region. At the same time, a acomprehensive introduction of energy saving coating glass, especially low emission（Low-E） coating glass has been given including the development, energy saving characteristic, types and preparation methods.In this paper, studied as low emission coating films, TiN films were deposited on the glass substrates by atmosphere pressure chemical vapor deposition（APCVD） method under low temperature, using TiCl4 and ammonia as precursors, N₂ as carrier gas. The films were characterized by means of XRD, SEM, TEM, XPS and UV-VIS-NIR spectroscopy and so on. It has been studied synthetically that the relationship between the structure of TiN films, composition, photoelectrical properties and the deposition parameters such as the substrate temperature, deposition time, density of TiCl₄ and density of ammonia. All films prepared by this method are polycrystalline films with NaCl type structure. With the increasing of the substrate temperature, deposition time and the content of reactant, the thicker film can be deposited, which benefit the crystallization of TiN crystals. But too high thickness and high density of TiN films will do harm to the smoothness of film surface with impurity deteriorating the crystallization.A detailed analysis of the electrical properties of TiN films has been carried out in order to investigate the preparation parameters influences on the films. It showed that the conductive mechanics was like metal’s. So its electrical properties was dependent on the microstructure of TiN film and the growth conditions of TiN film. And there were two factors to increase the electrical resistivity. One was cavity, and the other was impurity（especially oxygen）. Both were effective scattering center. Excessive impurity and cavity will lead to the impurity scattering of electron. Moreover, The infraredreflection rely much on the carriers concentration and Hall mobility in the films. Improving the carriers concentration and Hall mobility, decreasing the sheet resistance will enhance of the infrared reflection of the TiN films.The result showed that the sheet resistance of TiN films is 34. 5 , the tansimittance of TiN films is 65% in visible region and the infared reflection of TiN films is 60%.Based on these above, it is possible to regard TiN films as the new type of low emission coating films. The experimental results of optical properties and chemical stability show that the glass have improved its thermal insulation property and lead to energy saving ability. More than that, the visible transmission and reflection of this glass have been optimized.更多还原