Multiscale simulation of resist pattern shrinkage during scanning electron microscope observations

Multiscale simulations were performed to study poly(methyl methacrylate) (PMMA) resist pattern shrinkage by electron irradiation. Shrinkage of the patterns, which ranged from several micrometers to sub-10 nm in initial size, was simulated. The decrease in film thickness of a several micrometers-thick PMMA resist during scanning electron microscope observations was evaluated by a Monte Carlo simulation of electron scattering. A simple molecular dynamics simulation was developed to analyze sub-10-nm-wide PMMA resist pattern shrinkage by electron irradiation. The shrinkage of several tens of nanometers-wide PMMA resist patterns was also simulated by combining molecular dynamics and Monte Carlo simulations.