Analysis of the nanoimprint lithography with a viscous model

Nanoimprint lithography has attracted broad interest as a low cost method to define nanometer scale patterns in recent years. This method is also known as hot embossing lithography due to its inherited process technique from the hot embossing process. Success of the Nanoimprint lithography process relies on the adequate conditions of pressure, temperature, and time. To have the right conditions for Nanoimprint lithography, one has to understand the polymer flowing behavior during the imprinting process. In this study, a simulation model was developed based on a viscous fluid to predict the polymer flow behavior during the imprinting. The predicted flow patterns are qualitatively similar to the experimental result under an isothermal condition. For a constant imprint rate, the pressure does not change much at the beginning, but rises to a higher value as the tool base touches the polymer. The high pressure is caused by the induced polymer flow along the entire area. The wave-like polymer front was also predicted to travel out from the imprint patterns.