Etching 3-dimensional Photonic Crystals in GaAs

摘要

We present an efficient method for the fabrication of three-dimensional photonic crystals in GaAs-based materials. The method exploits the dependence of the oxidation rate of AlGaAs on the aluminum content in the alloy. As a result, a wide range of oxidation profiles is possible. The oxidation profiles are determined by the Al concentration profiles in a GaAs/AlGaAs stack grown by molecular beam epitaxy, and the resulting three-dimensional structure depends on the initial two-dimensional pattern defined by standard lithography. We detail the process and present preliminary results showing the viability of the method to realize three-dimensional photonic crystals of various geometries.