AS GROWN BI2SR2CACU2OY FILMS BY AN OFF-AXIS RF MAGNETRON SPUTTERING

Bi2Sr2CaCu2Oy (BSCCO) films were in intu grown by an off axis rf magnetron sputtering. The sputtering targets were stoichiometric Bi2Sr2CaCu2Oy compounds. The sputtering gas was a mixture of O2 and Ar and the sputtering pressure varied from 50 - 100 mTorr. The films were grown at 570 - 600-degrees-C. After growth the films were quickly cooled down to 300 K in 30 minutes. One found that the distance from the substrate to the target d is an important factor in affecting the deposition rate of the as grown BSCCO films. By reducing the distance d to 3 cm, we have achieved a deposition rate of about 1500 angstrom per hour in a sputtering power of 60 watts and sputtering pressure of 70 mtorr. With optimum growth conditions where the substrate temperature was kept at 580 - 600-degrees-C and the pressure was kept at 70 - 80 mTorr, superconducting BSCCO films with zero resistance at 75 - 85 K can be reproduced.