Post deposition annealing of epitaxial $\mathrm{Ce_{1−x}Pr_{x}O_{2-\delta}}$ films grown on Si(111)

Abstract

n this work the structural and morphological changes of Ce$_{1−x}$Pr$_{x}$O$_{2-\delta}$ (x= 0.20, 0.35 and 0.75) films grown on Si(111) due to post deposition annealing are investigated by low energy electron diffraction combined with a spot profile analysis. The surface of the oxide films exhibit mosaics with large terraces separated by monoatomic steps. It is shown that the Ce/Pr ratio and post deposition annealingtemperature can be used to tune the mosaic spread, terrace size and step height of the grains. The morphological changes are accompanied by a phase transition from a fluorite type lattice to a bixbyite structure. Furthermore, at high PDA temperatures a silicate formationvia a polycrystalline intermediate state is observed