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.
Citation: Optics Letters
Pub Type: Journals
Optical microscope, TSOM, Nano-metrology, Micro/nanotechnology, Semiconductor technology, Biotechnology, Process control, Defect analysis, Nano-manufacturing.