Structural characteristics of CeO2 films grown on biaxially textured nickel (001)

Preferential (001) orientation CeO2 films have been successfully grown on biaxially textured Ni substrates using ion beam assisted pulsed laser deposition. The x-ray diffraction (XRD) patterns for the CeO2 films and target have been measured. The in-plane lattice constants have been derived from the data of XRD. It was found that the in-plane lattice constants of the films increase with increasing deposition temperature. A reasonable explanation based on the difference of the linear thermal expansion coefficient between the CeO2 film and Ni substrate was proposed. Moreover, Raman spectra of the films and target have been recorded. It was shown that the oxygen deficiency in the CeO2 samples has a great effect on the full width at half maximum of the Raman lines. According to the relation between the Gruneisen shift and the lattice contraction, we have obtained the theoretical Raman shifts which are in good agreement with the experimental results.