Temperature-reduced nanoimprint lithography for thin and uniform residual layers

Abstract

Imprint processes can be described by the equations of squeezed flow. In case they account, in a modified form, for the filling of the stamp cavities during the imprint process they predict that the imprint activity virtually stops after complete filling of these cavities and a thick residual layer remains. Without cavity filling no interference of the imprint process occurs and very thin residual layers are obtained. This concept of partial cavity filling is tested during the imprint of fields of periodic 200 nm lines, and the imprint temperature was reduced to prevent the formation of self assembly induced defects. Very low residual layers and good aspect ratios were obtained even at temperatures of 130 °C for commercial polystyrene with a glass temperature of 105 °C.