Measurement of geometrical dimensions using scanning electron microscopy

In this paper, in-process measurement method of geometrical dimensions of fine patterns using the principle of stereoscopy and digital image processing techniques is presented. We have applied this measurement method to sub-micrometer patterns with variable shapes in fabrication steps. Then, we have verified that an accuracy of 0.063 μm and a repeatability of 0.14 μm in depth measurements of hole patterns with a sharp side wall angle, an accuracy of 0.75° and a repeatability of 0.53° in measurements of a taper angle of photoresist patterns were achieved.