Micro-fabrication of 3D square spiral photonic crystals using direct laser writing

Abstract

The ability to construct large-scale three-dimensional microstructures efficiently and economically finds many applications in the field of MEMS, bioscience, microelectronics and optics. In photonics, 3D photonic crystals in recent years have attracted great research interests due to their novel optical properties. Fabrication of three-dimensional photonic crystals is a challenging task, as it entails microstructuring large-scale periodic structures with resolution comparable to the optical wavelength. Here we report fabrication of photonic crystals by means of direct laser writing to record extended periodic arrays of square spiral structures that are shrinkage-free and having submicrometric resolution in a commercially available negative photoresist SU-8.