Slab Polymer Photonic Crystals

摘要

Photonic crystals enable a reduction in the size of current photonic devices by virtue of forbidden propagation, except along engineered lines of defects. Furthermore, propagation above the band-gap has unique characteristics such as the superprism effect. Polymer materials which typically suffer from low optical confinement can benefit from photonic crystal structures to increase integration and functionality. Due to its unique advantages, several authors have reported attempts at fabricating photonic crystal structures in polymer materials. However, a clear photonic bandgap (PBG) was not demonstrated. In this paper we describe our recent work in design, simulation and fabrication polymer photonics devices. We will discuss specific slab photonic crystal devices based on 2D hexagonally packed structures achieved in polymethyl-methacrylate films. Supercomputer simulations were used to target optimal geometries that consist of points in a three dimensional space of lattice parameter, hole diameter and slab thickness that enable a design of the photonic bandgap of the structure. Fabrication of the devices was achieved through use of high-resolution electron-beam lithography and etching. A robust air-clad polymer photonic crystal film was enabled by the additional support of a 40 nm-thin low-stress silicon nitride layer.