Thermal analysis for step and flash imprint lithography during UV curing process

Acrylate and vinyl ether monomers have previously been shown to be effective photocurable materials for step and flash imprint lithography. The photo polymerization of these monomer systems is exothermic. If the imprint process was adiabatic, the heat generated during polymerization could increase the temperature of the material to greater than 300 °C, possibly resulting in material degradation and image distortion. A finite element method was used to analyze the temperature profile during photopolymerization for non-adiabatic conditions. The heat from UV absorption is negligible because acrylate and vinyl ether imprint materials are transparent in the UV lamp exposure region and the loading of photo acid generator and photo radical initiator is low. This model indicates that the temperature increase from polymerization is very small (less than 0.05 °C) due to the rapid heat transfer from the curing material to the silicon wafer.