Effect of Magnesium on the Structural and Optical Characteristics of Thin Films of Zinc Oxide

The effects of magnesium on the morphology of a fi lm of zinc oxide, its crystal structure, and its optical characteristics were studied. It was shown that with magnesium concentrations of up to 12% the zinc ions are substituted by magnesium ions without rebuilding the crystal lattice. The optical conductivity of the samples in the range of 1–4 eV was calculated from the experimental ellipsometric parameters ψ and Δ. It was shown that there is an impurity band (due to the magnesium ions) in the optical conductivity difference spectrum. The decrease at magnesium concentrations of more than 8% is explained by biaxial stresses in the Mg x Zn 1 − x O films.