Zero-alignment method for tunable fabrication of three-dimensional photonic crystals by multiple-exposure laser interference using diffraction gratings patterned on a single mask

摘要

A method for fabricating three-dimensional photonic crystal structures includes providing a layer of photosensitive material; introducing a laser beams into the material; reintroducing the laser beams into the photosensitive material during a second exposure; combining results from at least the first and second exposures to produce a three-dimensionally periodic pattern in the photosensitive material. A related system includes a laser source; a grating array having a plurality of diffraction gratings located thereon; a mask plate located on a photoresist layer and arranged in registration with the grating array; a rotating shutter arranged between the grating array and the laser source, said rotating shutter being suitable for periodically blocking light from the laser source; wherein each of the diffraction gratings is positioned and oriented so as to converge all first-order diffracted spots to a common point lying in a plane of a back side of the mask plate.