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Through-focus scanning optical microscope imaging method for nano-scale dimensional analysis
Published
Author(s)
Ravikiran Attota, Richard M. Silver
Abstract
We present a novel optical technique that produces nanometer dimensional measurement sensitivity using a conventional bright-field optical microscope, by analyzing two-dimensional through-focus scanning optical microscope (TSOM) images constructed using a set of images obtained at different focus positions. The TSOM images enable one to (i) positively identify the dimension that is different between two nano-sized targets, (ii) determine magnitude of its difference, and (iii) determine the actual dimension by a library matching method. This methodology has potential usefulness for a wide range of targets, geometries and application areas, including, nano-metrology, micro/nanotechnology, semiconductor technology, biotechnology, process control, defect analysis, and nano-manufacturing.
Attota, R.
and Silver, R.
(2008),
Through-focus scanning optical microscope imaging method for nano-scale dimensional analysis, Optics Letters, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=824668
(Accessed October 11, 2025)