Research On The Automatic Ellipsometer Based On Photometric & Unite Method

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;...