Characterization of yttria-stabilized zirconia coatings with controlled nanometer-sized porosity by SANS

Abstract.

Coatings of cubic yttria-stabilized zirconia (YSZ) grown on alumina (Al₂O₃) substrates were characterized with regard to structure, grain morphology and porosity. The present study shows that the deposition of YSZ films onto polycrystalline Al₂O₃ substrates by MOCVD (metal organic chemical vapor deposition) under the given deposition conditions leads to nanostructured film morphologies with mean grain sizes in the range 10–14 nm when the substrate temperature is 450–550 °C. Small angle neutron scattering (SANS) was applied to analyze the pore structure in the nanometer range, revealing that the films have a pronounced, very finely dispersed porosity. For substrate temperatures ranging from 425–500 °C the average pore diameters are between 0.7 and 1 nm. For higher substrate temperatures, the pore size increases, reaching an average diameter of 5.4 nm at a substrate temperature of 600 °C.