Heteroepitaxial Growth of Nanostructured Cerium Dioxide Thin Films by MOCVD on a (001) TiO₂ Substrate

The deposition of epitaxial CeO 2 nanostructured thin films on rutile (TiO 2 ) substrates by metal−organic chemical vapor deposition (MOCVD) has been carried out in a wide temperature range. Films have been grown on (001)TiO 2 from the Ce(III) 1,1,1,5,5,5-hexafluoro-2,4-pentanedionato diglyme adduct (Ce(hfa) 3 ·diglyme). The X-ray diffraction patterns of all samples grown in the 450−750 °C deposition temperature range point to the formation of 〈100〉-oriented CeO 2 films, whereas at higher deposition temperatures (850−1050 °C) all the deposited CeO 2 films show 〈111〉 texture. fwhm rocking curves values clearly indicate that the texturing of CeO 2 crystallites is greatly improved upon increasing the deposition temperature in both cases. Typical pole figure patterns demonstrate a cube-on-cube epitaxial growth in the case of 〈100〉-oriented CeO 2 films, whereas 〈111〉-oriented CeO 2 films show different in-plane alignments of the crystallites. A possible explanation for textural changes is proposed.