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

High density plasma etching of zinc selenide using CH4/H-2/Ar plasma chemis tries is investigated. Mass spectrometry, using through-the-platen sampling , is used to identify and monitor etch products evolving from the surface d uring etching. The identifiable primary etch products are Zn, Se, ZnH2, SeH 2, Zn(CH3)(2), and Se(CH3)(2). Their concentrations are monitored as ion an d neutral fluxes (both in intensity and composition), ion energy, and subst rate temperature are varied. General insights about the surface chemistry m echanisms of the etch process are given from these observations. Regions of process parameter space best suited for moderate rate, anisotropic, and lo w damage etching of ZnSe are proposed.