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Praseodymium aluminum oxide (PrAlOx) thin films have been grown by metal organic chemical vapor deposition (MOCVD) using two different multimetal sources consisting of mixtures of aluminum acetylacetonate (Al(acac)3) with two praseodymium precursors, namely, the praseodymium hexafluoroacetylacetonate diglyme adduct (Pr(hfa)3âdiglyme) and the praseodymium tetramethylheptanedionate (Pr(tmhd)3). Smooth and amorphous films have been deposited on Si(100) substrates. Their chemical composition and microstructure, investigated by EDX measurements and TEM analyses, are deeply affected by the nature of the precursor mixture. Optimal structural and compositional properties are achieved with a Al(acac)3-Pr(hfa)3âdiglyme mixture. Annealing procedures at 900 °C under an inert ambient atmospher do not affect the film crystallization. Preliminary electrical characterizations indicate a dielectric constant of about 12.

The deposition of epitaxial CeO2 nanostructured thin films on rutile (TiO2) substrates by metal-organic chemical vapor deposition (MOCVD) has been carried out in a wide temperature range. Films have been grown on (001)TiO2 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 450-750degreesC deposition temperature range point to the formation of -oriented CeO2 films, whereas at higher deposition temperatures (8501050degreesC) all the deposited CeO2 films show texture. fwhm rocking curves values clearly indicate that the texturing of CeO2 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 -oriented CeO2 films, whereas -oriented CeO2 films show different in-plane alignments of the crystallites. A possible explanation for textural changes is proposed.

High-quality epitaxial LaAlO3 thin films have been obtained on SrTiO3 (100) substrates by metal−organic chemical vapor deposition (MOCVD) adopting an in-situ strategy which uses a liquid single source consisting of the second-generation La(hfa)3·diglyme (Hhfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedione, diglyme = bis(2-methoxyethyl)ether) precursor and Al(acac)3 (Hacac = acetylacetone). The LaAlO3 films, 400 nm thick, are strongly c-axis oriented with a ∼0.4° fwhm of the rocking curve [(200) reflection]. Pole figures provide indication of good in-plane texture.

MOCVD has been applied to the first successful deposition of CeO2 〈100〉 oriented films on no-rolled Hastelloy C276. The presently found columnar grain morphologies have been related to the zone model proposed by Mochvan and Demchishin for physical vapor deposition processes. The fiber texture strongly depends on the deposition temperature.