Fabrication of polymer photonic crystals using nanoimprint lithography

Dense two-dimensional periodic photonic bandgap structures are produced in poly(methyl methacrylate) thin films using nanoimprint lithography (NIL). The stamp original was made by electron beam lithography. Then, a high versatility of the process was achieved by fabricating copies of the stamp original via NIL, which enables varying and optimizing both fill factors and aspect ratios independently. For reliable stamp copying over the whole structural areas, the nanorheological behaviour had to be considered. Using those stamp copies, polymeric photonic band gap structures with an aspect ratio as high as 2 were successfully replicated.