透明衬底透明膜椭偏数据处理分析

为了解决迭代法在反演透明衬底透明膜找偏参量时的出错问题,采用理论与实验相结合的方法,对透明衬底透明膜椭偏数据处理进行了理论分析和实验验证,找到了当薄膜折射率接近衬底折射率时,椭偏数据反演就会出错的原因。据此提出了分段遍寻迭代搜索法,以LABVIEW为开发工具,成功设计和编写了相应的数据处理程序,最后对一些样品进行了实际测量反演并与文献结果作了比较。结果表明,该程序能正确反演透明衬底单层透明膜的参量,并具有反演速度快、精确度可达0.03nm、稳定性好等特点。

Discussion of iteration in the ellipsometry data processing of transparent film on the transparent substrate

When calculate the ellipsometry parameters of the transparent film on the transparent substrate , there may be a local minimum error, and analyse the cause of error. Analyse the root of equation, when the refractive index of film is less or greater than the refractive index of substrate; and draw up the graph of the equation root, gain the condition of single extreme or double extreme. According to the above analysis, present a subsection ransacking method and it can avoid possible error. with the help of Labview, a subsection ransacking program is successfully designed. Finally, measure some samples with the program, the result of measure is credible. Compare the result of measure with data on paper, it show that the question of the data processing about transparent film on transparent substrate is successfully settled; and it have the characteristic of inversion with speed, high precision, good stability and so on.