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TSOM Method for Semiconductor Metrology



Ravikiran Attota, Ronald G. Dixson, John A. Kramar, James E. Potzick, Andras Vladar, Benjamin D. Bunday, Erik Novak, Andrew C. Rudack


Through-focus scanning optical microscopy (TSOM) is a new metrology method that achieves 3D nanoscale measurement resolution using conventional optical microscopes; measurement sensitivities are comparable to what is typical using Scatterometry, SEM and AFM. TSOM can be used in both reflection and transmission modes and is applicable to a variety of target materials and shapes. Nanometrology applications that have been demonstrated experimentally or through simulations include defect analysis, inspection and process control; critical dimension, photomask, overlay, nanoparticle, thin film, and 3D interconnect metrologies; line-edge roughness measurements, and nanoscale movements of parts in MEMS/NEMS. Industries that could benefit include semiconductor, data storage, photonics, biotechnology, and, nanomanufacturing. TSOM is relatively simple and inexpensive, has high throughput, and provides nanoscale sensitivity for 3D measurements with potentially significant savings and yield improvements in manufacturing.
Proceedings Title
SPIE Advanced Lithography
Conference Dates
February 28-March 3, 2011
Conference Location
San Jose, CA
Conference Title
Metrology Inspection and Process Control


TSOM, through focus, optical microscope, nanometrology, process control, nanomanufacturing, nanoparticles, overlay metrology, critical dimension, defect analysis, dimensional analysis, MEMS, NEMS, photonics


Attota, R. , Dixson, R. , Kramar, J. , Potzick, J. , Vladar, A. , Bunday, B. , Novak, E. and Rudack, A. (2011), TSOM Method for Semiconductor Metrology, SPIE Advanced Lithography, San Jose, CA, [online], (Accessed June 22, 2024)


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Created April 18, 2011, Updated February 19, 2017