EFFECT OF SPUTTERING PARAMETERS ON RF-SPUTTERED YBCO THIN-FILMS

YBCO films were grown by rf diode sputtering using single composite target. The sputtering parameters have a profound effect on the growth kinetics of the film. The stoichiometry of the film usually differs from that of the target. The problem encountered in general is related to the resputtering (and erosion) of the film due to bombardment of energetic particles. The stoichiometry and thickness uniformity of the films on substrates located radially under the target have been studied systematically for different target-substrate distances. The effects of resputtering have been minimised by optimising this distance. We have also examined the effect of annealing and stoichiometric composition on the superconducting properties of these thin films.