Preparation and characterization of yttrium barium copper oxide high transition temperature superconducting thin films by MOCVD with single mixed precursors

Metalorganic chemical deposition (MOCVD) is a very complex process. For thin film metalorganic chemical vapor deposition, a simplified MOCVD system using single organometallic precursors demonstrated good performance. A model of the vaporization and mass transport of mixed organometallic compounds from single source for thin film metalorganic chemical deposition is presented. A stoichiometric gas phase can be obtained from a mixture of the precursors in the desired mole ratios, in spite of differences in the volatilities of the individual compounds. Proper film composition is obtained by controlling the velocity of a carriage containing the precursors through the heating zone of a vaporizer. The key point to obtain good composition control was to keep the organometallic precursor absolutely dry. YBCO superconducting films were prepared on YSZ(001) and MgO (100) substrates by single source MOCVD using a mixture of powders of Y(thd)...