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Through-focus Scanning Optical Microscopy



Ravikiran Attota


Through-focus scanning optical microscopy (TSOM) method provides three-dimensional information (i.e. the size, shape and location) about micro- and nanometer-scale structures. TSOM, based on a conventional optical microscope, achieves this by acquiring and analyzing a set of optical images collected at various focus positions going through focus (from above-focus to under-focus). The measurement resolution is comparable to what is possible with typical light scatterometry, SEM and AFM. One of the unique characteristics of the TSOM method is its ability to separate different dimensional differences (i.e. ability to distinguish, for example, linewidth difference from line height difference), and hence is expected to reduce measurement uncertainty. TSOM holds the promise of high-throughput through comparative measurement applications for wide variety of interdisciplinary areas with potentially significant savings and yield improvements.
Proceedings Title
Scanning Microscopies 2011
Conference Dates
April 25-29, 2011
Conference Location
Orlando, FL
Conference Title
Scanning Microscopies 2011: Advanced Microscopy Technologies for Defense, Homeland Security, Forensic, Life, Environmental, and Industrial Sciences" conference have accepted your paper, "Pursuit of clean SEM and HIM


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


Attota, R. (2011), Through-focus Scanning Optical Microscopy, Scanning Microscopies 2011, Orlando, FL, [online], (Accessed April 17, 2024)
Created December 31, 2011, Updated February 19, 2017