High aspect ratio etching of GaSb/AlGaAsSb for photonic crystals

Abstract

ABSTRACTPhotonic crystal structures defined by interferometric lithography were etched into GaSb and AlGaAsSb with 90% Al content using Inductively Coupled Plasma (ICP) Reactive Ion Etching (RIE) with BCl3 and BCl3/Ar gas mixture. Effects of DC bias, hole diameter, etch time and gas composition, on the etch rate of GaSb were investigated. Hardened photoresist (PR) was used as an etch mask for the experiments.