Property characterization of solid-solution semiconductor Zn1-xMgxS films

The solid-solution semiconductor Zn1-xMgxS thin films were grown by vacuum co-evaporation of ZnS and Mg powders on quartz glass substrate. The influence of the film growth conditions and Mg content on the microstructures of the Zn1-xMgxS films was studied. Its electronic structures were characterized with X-ray diffraction (XRD), X-ray energy dispersive spectroscopy (EDS) and ultraviolet visible (UV-Vis) absorption spectroscopy. The results show that the stoichiometry of Mg, x, in the Zn1-xMgxS films significantly affects the lattice constant, a, and the optical energy gap, Eg, of the Zn1-xMgxS films. By using Vegard law, two equations were experimentally derived: a(x)=0.53965-0.01415x(nm) and Eg(x)=0.853x2+0.086x+3.662(eV).