Characterization of the CH4/H-2/Ar high density plasma etching process forHgCdTe

High density plasma etching of mercury cadmium telluride using CH4/H-2/Ar p lasma chemistries is investigated. Mass spectrometry is used to identify an d monitor etch products evolving from the surface during plasma etching. Th e identifiable primary etch products are elemental Hg, TeH2, and Cd(CH3)(2) . Their relative concentrations are monitored as ion and neutral fluxes (bo th in intensity and composition), ion energy and substrate temperature are varied. General insights are made into surface chemistry mechanisms of the etch process. These insights are evaluated by examining etch anisotropy and damage to the remaining semiconductor material. Regions of process paramet er space best suited to moderate rate, anisotropic, low damage etching of H gCdTe are identified.