Inductively coupled plasma reactive ion etching of ZnO using BCl3-based plasmas

Etching characteristics of ZnO are investigated by means of inductively coupled plasma (ICP) reactive ion etching in BCl3-based plasmas. Etch rates are studied as a function of BCl3/Cl2/Ar chemistries, substrate temperature, ICP coil power, rf power, and working pressure. Surface profilometer, scanning electron microscopy, and atomic force microscopy are used to characterize etch rates, etch profiles, and the surface morphologies of etched samples. It is shown that the etch rate is determined by the BCl3 content in the plasma. Auger electron spectroscopy results demonstrate that the BCl3-based etching process produces negligible changes in the surface stoichiometry of ZnO.