Adjusting Astigmatism on Right-Angle Features and Surface Texture

Ideally you want to adjust astigmatism using features that are approximately circular, but sometimes your sample will not provide that option. This video gives some tips on how to fix astigmatism using right-angle features and/or the nanoscale-order surface texture of a device layer. More appropriate features may become visible after one iteration of alignments. The operator is encouraged to reevaluate the choice of alignment feature at this point.
Disclaimer: This video intended to serve as supplemental information and cannot replace in-person instrument training. Microscope operators are encouraged to consider which parameter setting is most suitable for their measurements. Caltech and KNI are not responsible for how the presented information is translated for use in other facilities.