Influence of oxygen on characteristics of Zn(O,S) thin films deposited by RF magnetron sputtering

Zn(O,S) thin films were successfully deposited by reactive sputtering using Ar and O-2 gas mixtures at 473 K. X-ray diffraction patterns revealed that the well crystallized Zn(O,S) films were deposited with increasing oxygen concentration in O-2/Ar, resulting in a shift of the Zn peak of 28.5 degrees to a higher angle, closer to the ZnO peak of 34.4 degrees. Zn(O,S) films were composed of grains agglomerated from small particles, which grew gradually with increasing oxygen concentration. The depth profiles and energy dispersive spectroscopy results of the films indicated that the O/(O+S) ratio increased from 0.04 to 0.81, and all Zn(O,S) films were Zn rich with uniform concentrations of each component. X-ray photoelectron spectroscopy revealed that, as the oxygen concentration increased to 2%, the ZnS films were transformed to Zn(O,S) films via substitution of oxygen for sulfur. (C) 2015 American Vacuum Society.