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Through-focus scanning optical microscope imaging method for nano-scale dimensional analysis



Ravikiran Attota, Richard M. Silver


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.
Optics Letters


Optical microscope, TSOM, Nano-metrology, Micro/nanotechnology, Semiconductor technology, Biotechnology, Process control, Defect analysis, Nano-manufacturing.


Attota, R. and Silver, R. (2008), Through-focus scanning optical microscope imaging method for nano-scale dimensional analysis, Optics Letters, [online], (Accessed May 22, 2024)


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Created September 1, 2008, Updated February 19, 2017