TSOM

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Through-Focus Scanning Optical Microscopy (TSOM) is an imaging method that produces nanometer-scale three-dimensional measurement sensitivity using a conventional bright-field optical microscope. TSOM has been introduced and maintained by Ravikiran Attota [1] at NIST. It was given an R&D 100 Award in 2010. [2] In the TSOM method a target is scanned through the focus of an optical microscope, acquiring conventional optical images at different focal positions. The TSOM images are constructed using the through-focus optical images. A TSOM image is unique under given experimental conditions and is sensitive to changes in the dimensions of a target in a distinct way, which is very well applicable in nanoscale dimensional metrology. The TSOM method is alleged to have several nanometrology [3] [4] [5] [6] [7] [8] applications ranging from nanoparticles to through-silicon-vias (TSV).

The National Institute of Standards and Technology, USA, produced a short Video on YouTube on the TSOM method.

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References

  1. "Dr. Ravikiran Attota". Archived from the original on 2016-06-16. Retrieved 2017-07-13.
  2. "Research & Development World".
  3. https://www.nist.gov/pml/div683/grp03/upload/tsom-ravikiran-attota.pdf [ bare URL PDF ]
  4. Ravikiran Attota, Ronald G. Dixson and Andras E. Vladár " Through-focus scanning optical microscopy ", Proc. SPIE 8036, Scanning Microscopies 2011: Advanced Microscopy Technologies for Defense, Homeland Security, Forensic, Life, Environmental, and Industrial Sciences, 803610 (June 1, 2011); http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=1265236 doi : 10.1117/12.884706
  5. Attota, R.; Bunday, B.; Vartanian, V. (2013). "Critical dimension metrology by through-focus scanning optical microscopy beyond the 22 nm node". Appl. Phys. Lett. 102 (22): 222107. Bibcode:2013ApPhL.102v2107A. doi: 10.1063/1.4809512 .
  6. Attota, R.; Dixson, R.G. (2014). "Resolving three-dimensional shape of sub-50 nm wide lines with nanometer-scale sensitivity using conventional optical microscopes". Appl. Phys. Lett. 105 (4): 043101. Bibcode:2014ApPhL.105d3101A. doi: 10.1063/1.4891676 .
  7. Attota, R.; Kavuri, P.P.; Kang, H.; Kasica, R.; Chen, L. (2014). "Nanoparticle size determination using optical microscopes". Appl. Phys. Lett. 105 (16): 163105. Bibcode:2014ApPhL.105p3105A. doi: 10.1063/1.4900484 .
  8. Kang, H.; Attota, R.; Tondare, V.; Vladar, A.E.; Kavuri, P. (2015). "A method to determine the number of nanoparticles in a cluster using conventional optical microscopes". Appl. Phys. Lett. 107 (10): 103106. Bibcode:2015ApPhL.107j3106K. doi:10.1063/1.4930994.