MgO and CaO stabilized ZrO2 thin films obtained by Metal Organic Chemical Vapor Deposition

Metal Organic Chemical Vapor Deposition of cubic stabilized zirconia was investigated by the addiction of the alkaline-earth oxides MgO and CaO. While Cp2ZrMe2 [(Cp=–C5H5, Me=–CH3)] was used as precursor for ZrO2, two different Mg compounds were tested for the MgO deposition, namely bis-(·5-methylcyclopentadienyl)Mg(II) [(Mg(Cp-Me)2] and bis-(2,2,6,6-tetramethyl-3,5-heptanedionate)(tetramethylethylenediamine) Mg(II) [Mg(tmhd)2·tmeda]. Bis-(2,2,6,6-tetramethyl-3,5-heptanedionate)(triethyleneglycoldimethylether)Ca(II) [Ca(tmhd)2·triglyme] was used for CaO growth. Depositions were carried out on fused quartz at 500 °C, yielding colorless and crack-free films well adherent to the substrates. A thorough characterization of their microstructure and chemical composition was obtained by the combined use of XRD (X-ray Diffraction), XPS (X-ray Photoelectron Spectroscopy) and EDXS (Energy Dispersive X-Ray Spectroscopy). The obtained results indicated a complete stabilization of zirconia in its cubic-fluorite phase when the magnesium and calcium content ranged from 12 to 30 at.% and from 17 to 38 at.%, respectively.