QQ客服 官方微博 反馈留言

题名	光学薄膜真空污染的探测、分析及控制
作者	凌波
学位类别	硕士
答辩日期	2007
授予单位	中国科学院上海光学精密机械研究所
导师	贺洪波
关键词	光学薄膜 杂质 污染 真空气氛 激光损伤阈值
其他题名	Detection, analysis and control of vacuum contamination in optical coatings
中文摘要	大量的薄膜激光损伤实验表明，薄膜中的杂质污染是导致薄膜激光损伤的重要诱因，抑制薄膜中污染的产生和缺陷的形成是提高其激光损伤阈值的一个主要途径。因此，探究薄膜污染的来源，分析其特性，寻找控制污染、抑制缺陷发生和发展的途径，对于不断提高薄膜的光学性能和抗激光强度，改进并扩展强激光系统在科研及生产中的应用，具有非常重要的意义。 本论文主要着重于研究真空镀膜过程中引入的杂质污染对光学薄膜性能的影响。 首先综述了目前光学薄膜中污染的主要来源及分类，以及针对污染常用的探测手段和控制方法，并介绍了杂质缺陷吸收模型以及杂质缺陷诱导激光损伤的机理。 采用残余气体四极质谱分析仪作为探测高真空室内污染的主要手段，系统地研究了镀膜过程中污染的来源，发展及其特性。实验证明，高真空系统内主要的污染有：水蒸气、油蒸气以及金属粒子。 实验研究了水蒸气对于真空镀膜气氛的影响，并结合了光谱分析、微结构分析、吸收测量和激光损伤阈值测量等手段，分析了水蒸气含量的高低对光学薄膜性能的影响。实验结果表明，水蒸气含量的降低有利于制备出致密度高、抗激光损伤能力强的光学薄膜。 通过对镀膜过程中对气氛的监控，发现真空结构材料是真空室内污染来源之一。黄铜材料不宜应用在高真空烘烤系统中，其材料的不稳定性会导致薄膜沉积过程中吸收性介质的形成，从而成为薄膜激光损伤的起始破坏点。 实验分析表明镀膜过程中的油污染主要来自于真空泵的返油以及高真空硅脂，且油污染是降低光学薄膜激光损伤阈值的重要因素之一。 针对真空室的水蒸气和油污染，提出外加冷凝捕集器以及抽气过程中充入干燥的高纯氮气的方法，可以有效降低真空气氛中的杂质含量，提高真空度，制备出高性能的光学薄膜。 此外，为了提高气氛含量分析数据的准确性，在残余气体质谱图定量分析方面，提出了气体灵敏度因子的校正方法，并简述了其测定方法和校正应用。
英文摘要	Numerous laser induced damage tests show that contamination is the most important inducement factor in laser-induced damage of optical coatings. Thus, exploring the origin of contamination, analyzing its characteristics and avoiding its development is of most significance in improving and expending the application of high-power laser systems in scientific research and manufacturing as well as in raising the optical performance and Laser-induced damage threshold(LIDT) of the coatings. The influence of impurities introduced during the vacuum coating process on the properties of optical coatings is the main research purpose of this thesis. The main sources and sorts of the contamination in optical coatings, general detection and control methods of such contamination were summarized at the beginning of the thesis. Then defect induced laser damage model and defect induced laser damage mechanism were introduced. By adopting the quadrupole mass spectrometer as the primary means to probe the contamination in the high vacuum chamber, we systematically investigate the source, development and characteristics of the contamination. The experiments indicated that there are three dominating contamination including water vapor, oil steam and metal particle. Experiments were done on studying the effect of water vapor content on atmosphere in vacuum coating chamber and the performance of optical coatings by means of spectral analysis, microstructure analysis, absorption and LIDT measurements. These measurement results showed that decreasing the water vapor content in vacuum chamber results in optical coatings with high packing density and LIDT. It is also found that vacuum structure material is one of the contamination sources when monitoring the vacuum atmosphere. Brass alloy is not suitable for high vacuum chamber with high temperature baking since its thermal instability will induce absorption medium forming in the coatings which is most probably be the initial point of laser induced damage. Based on the experiment results, the oil contamination during the coating process is mostly come from back-streaming of pump oil and high vacuum grease. Oil contamination is also proved to reduce the laser damage resistance of optical coatings. Appending cold trap and inflating dry and high-purity nitrogen are proposed to be effective means in decreasing the gas impurities such as water vapor and oil steam in vacuum atmosphere. Accordingly, high vacuum level and high-quality optical coatings can be achieved. Additionally, sensitivity factor as calibration technique was put forward to improve the quantitative analysis of residual gas. How to determining and utilizing the sensitivity factor are also briefly presented.
语种	中文
内容类型	学位论文
源URL	[http://ir.siom.ac.cn/handle/181231/16479]
专题	上海光学精密机械研究所_学位论文
推荐引用方式 GB/T 7714	凌波. 光学薄膜真空污染的探测、分析及控制[D]. 中国科学院上海光学精密机械研究所. 2007.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。