Development of 3-D measurement method based on projection moire for micro structure using SEM

利用阴影云纹的原理，已经提出了用扫描电镜进行三维测量的方法。该方法在条纹分析过程中必须将阴影云纹图像中的原始网格图像清晰地去除，才能进行高分辨率分析。提出了一种基于投影云纹原理的新方法来解决网格问题。本文讨论了该方法中反向散射电子束在物体表面产生网格阴影的机理。利用条纹扫描技术对作为网格阴影的条纹图像进行了分析。利用网格阴影现象实现了三维精确测量。此外，还测量了三维微观结构。通过与原子力显微镜结果的比较，证实了该方法具有高分辨率功率（约20nm）。

3-D measurement method by SEM has already been proposed by using the principle of shadow moire. In the method, the image of original grid in shadow moire image must be clearly removed in fringe analysis process in order to perform high resolution analysis. A new method based on the principle of projection moire is proposed to solve the trouble concerning the grid. In this study, the mechanism of producing some shadows of grid on the surface of the object by back scattering electron beam in the new method is discussed. Fringe image as shadow of grid is analyzed by Fringe scanning technology. 3-D precise measurement is realized by using the phenomenon of shadows of grid. Furthermore, a 3-D micro structure is measured. From comparison with results by AFM, it is confirmed that the proposed method has high-resolution power(about 20nm).