【作者】 张恒；

【导师】 黄佐华；

【作者基本信息】 华南师范大学 ， 光学， 2005， 硕士

【摘要】 椭圆偏振测量是通过分析偏振光在待测薄膜样品表面反射前后偏振状态的改变来获得薄膜材料的光学性质和厚度的一种光学方法。由于椭偏测量精度高和灵敏度高,具有非破坏性和非扰动性,被广泛应用于光学工业、电子工业、金属材料工业、化学工业及物理学、化学、生物学和医学研究等许多领域中。 本项目的研究内容涉及光机电算多学科的技术,是一个综合性的复杂探测系统。针对HST—1型椭偏仪存在的缺点和不足之处,对仪器系统进行了深入的研究,研究系统各个器件的运行参数和性能,使之最优化,能够达到更好的性能。本文工作成果主要有以下几个方面: (1) 构建了一套自动化椭圆偏振测量系统样机,研究了光机系统的各个组成部分,如光源、光学元件和光路等的特点及其对测量精确度的影响。 (2) 根据椭偏光度法原理,从理论上分析了光学元件不完善引入的误差,给出了影响光度法测量准确度的数据处理的修正公式,其中包括:光强本底噪声的消除、起偏器和检偏器的消光比影响、随机噪声的衰减等。 (3) 在理论及实验上尝试了在一次测量中使用光度法和消光法联合运用的可行性,缩短了测量时间提高了测量的准确度。 (4) 采用VC++软件平台,从新设计了主机测量和椭偏数据处理软件,保证了单层薄膜光学参数的反演精度。 (5) 完成了样机的安装和调试及主从机通讯接口的升级工作,发挥USB接口的即插即用和传输速度高等特点。 (6) 提出了双傅立叶变换,使光度法测量更加稳定和精确。 (7) 实现了样机的实时在线测量,数据处理和显示,为薄膜生长的实时监控提供了条件。更多还原

【Abstract】 Ellipsometry is an optical technology with which we are able to inspect optical properties and thickness of film. And its operation depends on the analysis of the polarization altered before as well as after polarized light reflecting upon the film. Owning to its brilliant precision, sensibility, non-destructiveness and non-perturbation, the ellipsometry is widely applied into the fields such as the optical industry, electronic industry, metal industry, chemical industry as wall as physics, chemistry, biology and medicine etc.The project concerning multiple disciplines of optics, mechanics, electronics and computation, makes a sound investigation into the system of the instrument with the aim at shortcomings existing in HST-1. The research on performance of all parts within the system enables the researchers to know how to run it in its best condition. The job done in this thesis is as follows:(1) A system of automated prototype ellipsometer is constructed, with a research on characters of all parts of the very system such as light source, optical elements and paths as well as their influence upon the precision of measuring;(2) According to the principle underlying the photometric method, this thesis improves the data processing revision formula, which betters precision of the former method by eliminating noise of environmental light, reducing random noises and modifying the data with extinction ratios of polarizer and analyzer;(3) Theoretically as well as experimentally, the try to apply the photometric method and the null method simultaneously into measuring is feasible, which shortens time and increases accuracy;(4) The VC++ software platform is used in the redesigning of host application software and data processing software, which enables us to enjoy high precision of optical parameters of single-layer film;(5) In this thesis, the installation and adjustment of prototype instrument as well as the upgrading of the interface between the master and the sliver is completed. USB exerts its brilliance in plug-and-play and high baud rate;(6) Double Fourier Transform proposed adopted in this thesis improve stabilization and precision of the photometric method;(7) The real-time investigation online, data processing and displaying are realized. This provides good conditions for real-time watching the growing of film;(8) The modification of table checking and direct calculating program shorten time of measuringin photometric method to between 2 and 4 seconds;(9) The prototype instrument is tested systematically. The results indicate that it is working well and enjoys higher precision than HST-1. The instrument can be used to measure film growing up on the surface of some materials;更多还原