Through-focus scanning-optical-microscope imaging method for nanoscale dimensional analysis

National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Optics Letters (Impact Factor: 3.18). 10/2008; 33(17):1990-2. DOI: 10.1364/OL.33.001990
Source: PubMed

ABSTRACT We present a novel optical technique that produces nanometer dimensional measurement sensitivity using a conventional bright-field optical microscope, by analyzing through-focus scanning-optical-microscope 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, semiconductor process control, and biotechnology.


Available from: Ravikiran Attota, Sep 23, 2014
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