In this article, a new scanning electron microscopy (SEM) image composition technique is de- scribed, which can significantly reduce drift-distortion related image corruptions. Drift-distortion commonly causes blur and distortions in the SEM images. Such corruption ordinarily appears when conventional image-acquisition methods, i.e. "slow scan" and "fast scan", are applied. The corrup- tion is often very significant; it may render images unusable for metrology applications, especially, when sub-nanometer accuracy is required. The described correction technique works with a large number of quickly taken frames, which are properly aligned and then composed into a single image. Such image contains much less noise than the individual frames, whilst the blur and deformation is minimized. Also, this technique provides useful information about changes of the sample position in time, which may be well used to investigate the drift properties of the instrument.
Citation: Microscopy and Microanalysis
Pub Type: Journals