Anisotropic Ion Beam Assisted Etching of Optical Structures in GaAs and InP

Abstract

ABSTRACTIon beam assisted etching (IBAE) was used to define submicron structures into GaAs/AlGaAs and InP/InGaAsP heterostructures. Etch rates in excess of I pm/minute were obtained after optimization of the etching process, allowing the fabrication of optoelectronic structures which require smooth, vertical sidewalls and depths of several microns. By altering the gas flow and the ion beam parameters, the same technique was used to pattern electron beam-written structures with lateral dimensions of less than 30 nm and aspect ratios in excess of 5:1 in GaAs.