J. Phys. IV France 02 (1991) C2-539-C2-548
HIGH-TC-SUPERCONDUCTORS PREPARED BY CVDF. SCHMADERER1, R. HUBER1, H. OETZMANN1 and G. WAHL2
1 Asea Brown Boveri AG, Corporate Research Heidelberg, P.O. Box 10 13 32, D-6900 Heidelberg 1, Germany
2 Technical University, Inst. f. surface Technology, Braunschweig, Gemany
YBa2Cu3O7-δ - deposition experiments were carried out in a cold wall stagnation flow CVD-reactor on single crystalline (100)-oriented SrTiO3-substrates at a total pressure of 10 mbar. As source materials different β-diketonate derivates of yttrium, barium and copper were investigated concerning their volatility and decomposition behaviour. Finally for the YBa2Cu3O7-δ deposition process Y(thd)3, Ba(thd)2 and Cu(thd)2 were used. The evaporation temperatures Tv were 112, 208 and 117 °C respectively. High quality films can be obtained with the c-axis perdendicular to the substrate surface at temperatures higher than 850 °C. The transition temperatures of the coatings are higher than 90 K and the critical current densities are in the order of jc = 106 A/cm2 at 77 K and self magnetic field.
© EDP Sciences 1991