Thermodynamic simulation of YBa2Cu3O6+x film growth using aerosol MOCVD

Future high power applications of high Tc superconducting materials (like YBa2Cu3O6+x) demand thick films with excellent electrical properties. The use of thin film deposition techniques is only possible when high deposition rates can be reached. A novel aerosol MOCVD technique using a liquid source has recently been developed and is very promising for this purpose. The precursor materials used are the β-diketonates of yttrium, barium and copper, dissolved in diethylene glycol dimethyl ether (''diglyme'') in various concentrations. A preliminary thermodynamic simulation of the process is a useful tool for a deeper understanding of the stability limits of the superconducting phase and the on-going reactions during deposition. The results of these simulations have been used to optimise the process conditions for YBa2Cu3O6+x growth with good superconducting properties. A comparison between the simulation and the experimental results will be given and the influence of the main process parameters (deposition temperature, oxygen partial pressure, precursor concentration, ..) will be shown. (orig.)