The effect of deposition rate on the microstructure of YBCO thin films prepared by inverted cylindrical magnetron sputtering

The dependence of YBCO thin film properties on the deposition rate was studied in this report. The thermodynamic growth parameters (substrate temperature, total pressure and oxygen partial pressure) were optimized at a fixed deposition rate first. Then keeping the thermodynamic growth parameters optimized values, YBCO thin films were deposited at different deposition rates. The effect of the deposition rate on the superconducting transition properties, c-axis lattice constant, concentration of lattice disorder and surface smoothness of YBCO thin films was studied. The measurements show that the optimized thermodynamic growth parameters are closely correlated to the deposition rate. At a fixed deposition rate of 0.5 Angstrom/s and its optimal thermodynamic growth parameters, YBCO thin films with superior superconducting transition temperature, the lowest concentration of lattice disorder, and the lowest surface roughness were prepared. By using the same thermodynamic growth parameters, changes in deposition rate were shown to degrade the superconducting transition temperature, increase the lattice disorder, and increase the roughness of the YBCO thin films. (C) 2001 Elsevier Science B.V. All rights reserved.