白光干涉术测量表面形貌, 解决了单色光干涉测量中的相位不确定困扰。基于扫描白光干涉术的空间频域算法, 具有受噪声影响小、计算精度高的优点。运用这一算法通过 Mirau扫描干涉显微镜对台阶状样品表面进行了两次白光扫描测试, 得出了台阶表面形貌结果, 且两次测量的台阶高度相差不超过 1 nm。同时, 利用 Zygo Newview 7200白光形貌仪对同一样品表面进行了测试对比, 结果表明:两者得到的样品表面形貌一致, 台阶高度相差 0.9 nm。此外, 实验数据处理的结果还表明:运用空间频域算法进行分析时二阶以上的色散完全可以忽略。

White light interferometry for topography measurement can avoid phase uncertainty trouble which exists in laser interferometry. Spatial Frequency Domain Algorithm (FDA), based on white-light scan interferometry, has the advantage of insensitivity to noise and higher calculation accuracy compared with other methods. Applying FDA, two white light scanning tests on the surface of a step-like sample are carried on with a Mirau typed scan interference microscope. Thus two stepped profile results are obtained, their step heights difference not exceeding 1 nm. Meantime, the same sample is also tested with a Zygo Newview 7200 profiler, both topography results agreeing with each other and step heights differing by 0.9 nm. Besides, data processing results also show that the chromatic dispersion higher than 2nd order is completely negligible when applying FDA.