Stochastic modeling in lithography: use of dynamical scaling in photoresist development

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 alpha and the growth exponent beta were found to match the 1+ 1 KPZ values exactly. (C) 2009 Society of Photo-Optical Instrumentation Engineers. [DOI: 10.1117/1.3158612]