ZrO2 Sol-Gel Thin Films by XPS

ZrO2 thin films were prepared by dip-coating on silica glass via sol-gel processing. Ethanolic sols of zirconium butoxide were used as precursors. The ZrO2 films were prepared under controlled atmosphere and resulted transparent, homogeneous, crack-free, and well adherent to the substrates under heating up to 900 °C. The composition of the films was investigated by x-ray photoelectron spectroscopy. In particular, the principal core levels were analyzed for the sample annealed for 1 h at 900 °C. The microstructure of the films was studied by glancing incidence x-ray diffraction as a function of the annealing temperature. The coatings were amorphous up to 400 °C and crystalline ZrO2 with tetragonal structure was observed at 600 °C. Nanostructured layers with an average crystallite dimension of 15 nm were obtained up to 900 °C.