SEM扫描云纹法相移技术在MEMS中的应用

Application of Phase Shifting Technique for SEM Scanning Moiré Method in MEMS

本文提出一种扫描电镜 ( SEM)扫描云纹法的相移新技术 ,通过 SEM系统控制电镜电子束扫描线移动 ,对获取的云纹图像实现 0～ 2π范围内的四步相移 ,从而获得了更高的位移测量灵敏度 .同时对 SEM相移实验技术的原理进行了详细的阐述 .并将该技术应用到微电子机械系统构件的虚应变分析中 .实验结果证明了该方法的可行性 。

A new phase shifting SEM scanning moiré method is proposed in this paper. The phase shifting technique is realized in four steps from 0 to 2π by shifting electron beam in y axis direction controlled by SEM system. It is successfully applied to measure the virtual strain of a MEMS structure with grating of 5000lines/mm. The experiments prove the technique can be widely used in meso deformation measurement, and also show the sensitivity of experiments is highly improved after phase shifting technique. It provides a new way for disposal of fringes pattern in sub micro moiré method.