Characterization of damage in reactive ion etched ZnTe

Reactive ion etching of ZnTe has been carried out at various applied rf powers and $CH4/H2$ concentrations. The damage induced during dry etching is characterized by low-temperature photominescence (PL) measurements. It is observed that the PL intensity of the free excitons decreases with increasing applied rf power, which is ascribed to the increase of the surface damage by ion bombardment. The amount of the surface damage can be reduced by adding more $CH4$ in the gas mixture due to the effect of chemical etching.