相移干涉法测量ICF微球内表面粗糙度

Interior surface roughness of ICF micro-shells with phase shift interference technique

通过分析光线通过微球壳层后各界面的相位分布,讨论了相移干涉法测量微球内表面粗糙度的基本原理,研究了微球上部壳层对内表面粗糙度测量的影响,得到了聚苯乙烯,聚α甲基苯乙烯微球的内表面形貌特征图像,测量数据与原子力显微镜测量数据在同一量级。以微球壳层对超光滑碳化硅及单晶硅片表面形貌的调制作用为研究对象,讨论了微球的外表面粗糙度以及微球壁厚对内表面粗糙度测量结果的影响,确定了相移干涉法测量微球内表面粗糙度的不确定度,实验结果表明:对于表面粗糙度小于30 nm、厚度小于9μm的微球,测量不确定度小于0.4 nm。

Phase-shifting interference（PSI） is an important method in surface roughness measurement. In this paper, on the basis of analyzing phase distribution of micro-shell interface, the measuring principle of interior surface roughness of micro-shells is discussed. Inner surface images of PS and PAMS micro-shells were obtained with PSI method. The results are consistent with the measured results by atomic force microscope. The measurement error is analyzed by studying the influence of thickness fluctuation of micro-shell and outer surface roughness of micro-shell on measured results of SiC and crystal Si surface roughness. The experimental result shows that the measuring uncertainty is under 0.4 nm for micro-shells with 30 nm outer surface roughness and 9 μm thickness.