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Nanoscale Measurements with a Through-Focus Scanning-Optical-Microscope



Ravikiran Attota, Richard M. Silver, Thomas A. Germer


We present a novel optical technique that produces nanometer dimensional measurement sensitivity using a conventional optical microscope, by analyzing through-focus scanning-optical-microscope (TSOM) images obtained at different focus positions. In principle, this technique can be used to identify which dimension is changing between two nanosized targets and to determine the dimension using a library-matching method. This methodology has potential utility for a wide range of target geometries and application areas, including, nanometrology, nanomanufacturing, defect analysis, semiconductor process control, and biotechnology.
Future Fab International


Through Focus, Scanning, Optical Microscope, Nanometrology, TSOM, Nanomanufacturing
Created July 15, 2009, Updated February 19, 2017