The concepts of dynamical scaling in the study of kinetic roughness are applied to the problem of photoresist development. Uniform, open-frame exposure and development of photoresist corresponds to the problem of quenched noise and the etching of random disordered media and is expected to fall in the Kadar-Parisi-Zhang (KPZ) universality class. To verify this expectation, simulations of photoresist development in 1+1 dimensions were carried out with random, uncorrelated noise added to an otherwise uniform development rate. The resulting roughness exponent α and the growth exponent β were found to match the 1+1 KPZ values exactly.
Chris A. Mack,
"Stochastic modeling in lithography: use of dynamical scaling in photoresist development," Journal of Micro/Nanolithography, MEMS, and MOEMS 8(3), 033001 (1 July 2009). https://doi.org/10.1117/1.3158612