Chemically assisted ion beam etching of GaAs, Ti, and Mo

Investigations with argon and chlorinated ion beams have shown that the etch rates of GaAs and Ti are strongly dependent on the flux of molecular and atomic chlorine. Etch rate increases were observed with an increase in the chlorine flux from the background gas composition or from the impinging ion beam. At increased chlorine concentrations in the presence of ion bombardment, wall profiles were altered from an overcut slope to nearly vertical. In the etching of Mo, etch rates were limited by the removal of low volatility chlorides by ion-assisted mechanisms.