EXAFS studies on Gd-doped ZrO₂ thin films deposited by RF magnetron sputtering

ZrO₂ thin films with 0%, 7%, 9%, 11%, and 13% Gd doping have been prepared by RF magnetron sputtering and have been characterized by grazing incidence x-ray diffraction, spectroscopic ellipsometry, and optical transmission measurements to probe their structural and optical properties. Extended x-ray absorption fine structure (EXAFS) measurements have also been carried out on the samples at the Zr K- and Gd L₃-edges. It has been observed that Gd goes to Zr sites up to 9%-11% doping concentration, and for Gd doping concentrations beyond 11%, Gd precipitates out as a separate Gd₂O₃ phase. The local structure information surrounding the Zr and Gd sites obtained from the analysis of the EXAFS studies have also been used to explain the macroscopic optical properties of the samples.