Importance of evaporation in the design of materials for step and flash imprint lithography

摘要

Step and flash imprint lithography is a low cost process capable of generating sub-50 nm patterns. Although the printing resolution is better than optical lithography, the throughput at the available production tools is lower, in part, due to the time required to fill the imprint template features. The throughput can be improved by lowering the viscosity of the imprint material and reducing the drop size. Decreasing viscosity generally increases the volatility of a material and decreasing drop size increases the area available for evaporation. This study compares measured and predicted rates for volatilization of aery late and vinyl ether monomers. The predicted rates are based on the methods of Lee-Kesler and Joback-Reid that employ group contributions. The predictions were used to explore the effect of drop size (200 nl, 1 nl, 80 pl) on evaporation rate at 20℃ for t-butyl acrylate, hexyl acrylate, ethylene glycol diacrylate, lauryl acrylate, r-pentyl vinyl ether, ethylene glycol vinyl ether, 1,4-butanediol divinyl ether, and triethylene glycol divinyl ether. The predicted rates correlate well with experiment.