3D photonic crystals fabricated by nanoimprint lithography

In recent years direct writing methods as e-beam lithography have been extensively used for research and development of photonic structures but these techniques cannot be easily scaled up for cost efficient production. The restrictions in pattern size and fabrication of 3D structures, in combination with long process time and high costs make high quality, nanoimprinting techniques an attractive solution for next generation lithography methods. There are several Nanoimprint Lithography (NIL) techniques which can be categorized depending on the process parameters and the imprinting method - either step & repeat or full wafer imprinting. A variety of potential applications has been demonstrated using NIL (e.g. SAW devices, vias and contact layers with dual damascene imprinting process, Bragg structures, patterned media) [1,2]. In this work UV-NIL has been selected for the fabrication process of 3D-photonic crystals. Results with up to five layers will be demonstrated.