Viscous flow simulation in nanoimprint using coarse-grain method

Sets of approximate equations that describe the resist flow under a nanoimprint lithography stamp are derived from 3D Navier–Stokes equations. Special finite-difference schemes are built. These schemes permit to apply by modeling a reasonable coarse grid. The obtained numerical model provides the calculation of imprinting pressures and velocities under several loading regimes: constant imprint velocity or constant applied force. Comparisons with experimental data result in a satisfying qualitative agreement. The analysis of these results led to the conclusion that quantitative correspondence may be achieved by further taking into account the deformation of the stamp.