中文摘要：

提出一种用于测量微结构表面形貌的离轴显微干涉术。该技术的实验装置为一个优化的马赫-曾德尔干涉仪。其特点为参考波是具有一定载频的倾斜波。该技术中应用CCD记录离轴显微干涉图,并用傅里叶变换方法对记录的干涉图在傅里叶面进行频谱滤波求解相位。不同于经典显微干涉术,离轴显微干涉图的载频较高,仅需单幅干涉图即可得到相位信息。因此该技术在测量中具有防振、快捷有效的特点。利用一个标准微台阶以及微孔阵列的形貌检测结果验证该技术的有效性,同时与轮廓仪的测试结果进行对比,证明结果一致。被测物也应用Mirau干涉显微镜进行测试,实验结果表明经典显微干涉图干涉信息载频不足,仅使用单幅干涉图不能得到正确相位,该组实验证明了离轴显微干涉术相对于传统显微干涉术的优越性。

英文摘要：

A technique called off-axis microscopic interferometry is developed to measure the surface profile of microstructures. This technique involves the use of a modified Mach-Zehnder microscopic interferometer with a tilted reference wave. The technique uses a CCD camera to record the off-axis microscopic interferogram and performs filtering in the Fourier plane via the Fourier transform method for phase retrieval. In contrast to classical microscopic interferometry, the carrier frequency of the off-axis microscopic interferogram is sufficiently high to facilitate acquisition of the phase from only one interferogram. As a result, measurements using this technique are vibration-immune and efficient. The experimental results obtained for a step height standard as well as a microhole array are consistent with measurements taken using a stylus profilometer. Further, the results of a comparative experiment conducted using a Mirau interferometric microscope show that the carrier frequency added to the classical microscopic interferogram cannot be as high as that of off-axis microscopic interferogram. Therefore,it will lead to incorrect phase retrieval with one interferogram.