Effect Of Varying Sputtering Power Levels On Y-Ba-Cu-O Film Composition

R.F. diode sputtering technique is used to deposit superconducting thin films of Y-Ba-Cu-O on various substrates from a single composite target. Sputtering power levels of 50, 100, and 150 W are used to study the effects of different power levels on the composition and deposition profiles of the films. The as-deposited films show a strong radial variation in composition. A circular ring like pattern with little or no film deposition in the center of the substrate is observed for all three power levels. This is believed to be due to the resputtering effects from negative ion and energetic neutral particle bombardment. Energy dispersive spectrum results indicate that copper is uniformly distributed across the substrate, compared to Ba which is deficient near the center of the substrate. Films deposited on SrTiO3 substrates exhibit regions of fractal growth which was 123 composition