Preparation of ZrO2-Y2O3 layers at low temperatures by MOCVD under atmospheric and reduced pressure

Non-porous amorphous or nanocrystalline ZrO2-Y2O3 layers were synthesized on quartz glass substrates using Zr(tmhd)4 and Y(tmhd)3 as reactants. The synthesis temperature was changed in the range of 520-820 °C. The total gas pressure in the CVD reactor amounted to approximately 760 mmHg or 50-80 mmHg. The molar ratio of Zr(tmhd)4::Y(tmhd)3 was approximately 6.2. Ar and air were used as carrier gases. Air fulfilled role of oxidizer of carbon resulting from the pyrolysis of metalo-organic reactants. The value of the gas flow was selected so that the extended criterion of Grx/Rex2 was below 0.01. The microstructures of layers deposited with and without the presence of air were examined by scanning electron microscopy. Their linear and average point chemical composition (from relatively the fracture of the sample and its surface) were determined using an EDS analyzer. The samples were also tested by X-ray analysis and UV-VIS spectroscopy.