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Optical Linewidth Models - Then and Now



Robert D. Larrabee, Richard M. Silver, M P. Davidson


In the late 1970's Dr. Diana Nyyssonen demonstrated that the National Institute of Standards and Technology (NIST) could optically calibrate photomask linewidth standards that were narrower than the classical resolution limit of a conventional bright-field microsope. She equated the unknown edge position on the line edge on the observed image to the known edge position on a theoretically calculated image profile of that line (taking diffraction into account). Since, at that time, there was no other way to accurately identify the position of the geometrical edge of the geometrical edge of micrometer-sized lines on their on their observed optical images, NIST would not have been able to issue accurate photomask linewidth standards without her theoretical model.
SPIE series


linewidth, metrology, modeling, photomask, standards


Larrabee, R. , Silver, R. and Davidson, M. (1999), Optical Linewidth Models - Then and Now, SPIE series (Accessed February 27, 2024)
Created March 1, 1999, Updated February 19, 2017