Characterization of oxygen impurities in thermally evaporated LaF3 thin films suitable for oxygen sensor

The lanthanum fluoride thin films has been prepared by means of thermal evaporation method. The XRD analysis shows the formation of polycrystalline hexagonal LaF3. The depth profile X-ray photoelectron spectroscopy (XPS) analysis shows the presence of oxide ions throughout the films. The formation of lanthanum oxyfluoride (LaOF) has been identified. The [O]/[F] ratio has been found to be 0.35 which is higher than the previously reported values of LaF3 film applied for the oxygen sensor. # 2003 Elsevier B.V. All rights reserved.