STRESS MODIFICATION IN SPUTTERED ZINC-SULFIDE AND ZINC OXYSULFIDE THIN-FILMS

The physical characteristics of zinc sulfide and zinc oxysulfide thin films deposited by rf magnetron sputtering have been studied. The stress and composition were functions of the deposition conditions. The stress could be independently controlled by two methods. Increasing the gas pressure did not alter the composition, but it did result in a change in the microstructure of the deposit that was accompanied by a reduction in the stress. Adding increasing amounts of oxygen to the sputter gas at constant pressure resulted in the formation of oxygen-containing compounds in the film that reduced the stress. Composition, chemical bonding, and structure were studied by a variety of techniques. The kinetics of oxygen incorporation were studied, and an atomic model was proposed.