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Multiple-order Imaging for Optical Critical Dimension Metrology using Microscope Characterization
Published
Author(s)
Jing Qin, Hui Zhou, Bryan M. Barnes, Francois R. Goasmat, Ronald G. Dixson, Richard M. Silver
Abstract
There has been much recent work in developing advanced optical metrology applications that use imaging optics for optical critical dimension (OCD) measurements, defect detection, and for potential use with in-die metrology applications. We have previously reported quantitative measurements for sub-50 nm CD dense arrays which scatter only the 0th-order specular diffraction component using angle-resolved scatterfield microscopy. Through angle-resolved and focus-resolved imaging, we now access the three-dimensional scattered fields from OCD targets that contain multiple Fourier frequencies. Experimental sensitivity to nanometer scale linewidth changes is presented, supported by simulation studies. A new, more advanced approach to tool normalization is coupled with rigorous electromagnetic simulations and library based regression fitting that potentially enables OCD measurements with sub-nanometer uncertainties for targets that scatter multiple Fourier frequencies.
Proceedings Title
Instrumentation, Metrology, and Standards for Nanomanufacturing IV, Proceedings of SPIE Volume: 7767
Qin, J.
, Zhou, H.
, Barnes, B.
, Goasmat, F.
, Dixson, R.
and Silver, R.
(2012),
Multiple-order Imaging for Optical Critical Dimension Metrology using Microscope Characterization, Instrumentation, Metrology, and Standards for Nanomanufacturing IV, Proceedings of SPIE Volume: 7767, San Diego, CA, [online], https://doi.org/10.1117/12.946120
(Accessed October 11, 2025)