Polarization analyses of aerial images produced by an optical lithography system.
The influence of polarization on the image formation of one-dimensional periodic patterns in a projection optical lithography system has been investigated. Assuming a linear polarizer at thelens pupil, I derived a simple expression representing the image intensity as the summation over spatial-frequency harmonics as well as three orthogonal polarizations. I calculated the coefficient for each image component as a function of the pattern frequency by independently varying the degree of partial coherence such that the image qualities of the two extreme polarization cases could be thoroughly compared.
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