Fabrication of three-dimensional polymer photonic crystal structures using single diffraction element interference lithography

The recording of three-dimensional periodic structures in a photosensitive polymer using a single diffraction element mask was reported. The central opening of the mask was surrounded by three diffraction gratings oriented 120° relative to one another such that the nondiffracted laser beam and the three first order diffracted beams give a 3D spatial light intensity pattern. It was found that masks with a 1.0 and 0.56 μm grating period, produce micron- and submicron-scale 3D features with good unifromity and definition over large substrate areas.