【作者】 冯丽萍；

【导师】 刘正堂；

【作者基本信息】 西北工业大学 ， 材料学， 2004， 硕士

【摘要】 蓝宝石所具有的一系列优异性能，决定了它是目前作为中波红外窗口与头罩的最有前途的材料。但是，限于目前的材料制备和加工技术水平，蓝宝石的高温强度大幅度下降，红外透过率也满足不了设计使用要求。因此在蓝宝石表面镀制增透保护涂层就成为满足其在高速、高温下应用的关键技术。氧化硅（SiO₂）膜具有优良的物理、化学性能，并且与蓝宝石附着良好，非常适合用作提高蓝宝石高温强度及增透涂层。在国外，SiO₂用作蓝宝石增透保护涂层的研究已经展开，并取得进展；而在国内，这方面的研究还未见报道。本文主要开展了蓝宝石衬底上氧化硅增透保护膜系的设计与制备工艺和性能研究，为将氧化硅用作蓝宝石头罩的增透保护涂层奠定了基础。主要研究成果如下： 利用OPFCAD软件在蓝宝石衬底上设计了SiO₂、SiO₂／Si等增透保护膜系，并对所设计的膜系进行了结构敏感因子（n，d）及结构偏差分析。设计结果表明，蓝宝石衬底双面镀SiO₂、SiO₂/Si等膜系，在3～5μm波段的平均透过率大于97％，可满足导弹头罩设计和使用的要求。 在BMS450型磁控溅射镀膜机上优化出了制备SiO₂薄膜的工艺参数范围，并揭示了气体流量、射频功率、靶基距、衬底温度、溅射气压等参数对薄膜沉积速率的影响规律。 利用射频磁控反应溅射法，在蓝宝石试片和半球形头罩上制备出所设计的SiO₂和SiO₂／Si增透膜系。蓝宝石衬底双面镀SiO₂膜，在3～5μm波段范围内，平均透过率达到96.43％，满足了导弹头罩的设计使用要求。 对所制备的SiO₂薄膜进行了X射线光电子谱（XPS）、X射线衍射（XRD）分析及高温退火处理。由XPS分析结果可知，薄膜中的Si、O元素形成了SiO₂化合物。XRD分析结果表明，所制备的SiO₂薄膜结构为非晶态；在800℃以下退火，薄膜的结构没有发生明显的改变，仍为非晶态。更多还原

【Abstract】 Sapphire has such excellent properties that it is superior to other current and emerging materials for window and dome applications. However, the current states of production and process of sapphire are not very well. The c-axis compressive strength of sapphire decreases dramatically at elevated temperature and the optical transmission cannot satisfy the demand of application and design. In order to meet the need for applications of high-speed or high-temperature, the anti-reflective and protective films need to be prepared on the sapphire surface. Silicon dioxide (SiO2) are promising anti-reflective films with good physical, chemical properties and good adhesion to sapphire. Great progress has been made in the researches about SiO2 anti-reflective and protective films overseas. But no domestic work has been done on SiO2 optical and protective films. Researches of the paper mostly concentrate on design and preparation of anti-reflective and protective films of SiO2 on sapphire. What’s more, we have studied the properties of the films. The work is base for SiO2 used as anti-reflective and protective coatings on sapphire dome. The main contents and results are listed as follows:With the help of OPFCAD software, anti-reflective and protective films of SiO2 and SiO2/Si are designed on the sapphire substrate and analysis of structure sensitive factor and variation are done. The results of design explain that if SiO2 films deposited on the surfaces of sapphire the average transmittance in 3~5 m waveband can exceed 97%, which can meet the requirements of missile dome in infrared application.SiO2 films are prepared on silicon substrates in order to get the functions of the main experiment parameters such as RF power, gas flow, vacuum gas pressure, target-substrate distance and substrate temperature on deposition rate of films. The optimized parameters ranges are obtained by considering films deposition rate, composition and structure.The designed films of SiO2 and SiO2/Si are prepared on sample and hemisphere dome of sapphire by radio frequency magnetron reactive sputtering method. The average transmittance at a wavelength of 3~5 m of sapphire coated with one layer of SiO2 antireflective films on two sides can reach 96.43%. So as to the transmittanceof coated sapphire can satisfy the demand of window and dome applications.XPS analysis as well as XRD and high temperature heat treatment are made. XPS results confirm the formation of SiO2. XRD results show that deposited SiO2 films are amorphous. Heat treatments explain that films are still amorphous as the temperature of heat treatment reach 800 .更多还原