Volatile Ce-III hexafluoroacetylacetonate glyme adducts as promising precursors for the MOCVD of CeO2 thin films

Three novel monomeric glyme adducts of cerium hexafluoroacetylacetonate (Ce(hfa)3odiglyme 1, Ce(hfa)3odiethyldiglyme 2, and Ce(hfa)3odibutyldiglyme 3) have been synthesized adopting a one-pot procedure and characterized by elemental analyses, mass spectrometry, and infrared spectroscopy. Single-crystal X-ray diffraction (XRD) studies provide evidence of a mononuclear nine-coordinated complex with a monocapped square antiprismatic structure of the Ce(hfa)3odiglyme (monoclinic system, space group = P21/c; a = 10.037(2) Å, b = 15.643(5) Å, c = 21.080(5) Å, ? = 103.460(5)°, Z = 4). The thermal analyses of all three compounds revealed high volatility and good thermal stability with low residue. The adducts 1-3 have better mass transport properties and thermal behavior than conventional cerium metal-organic chemical vapor deposition (MOCVD) precursors, and have been successfully applied to CeO2 film depositions. The good quality of the deposited layers indicates that the adducts are very attractive precursors for MOCVD applications.