Preparation of High-T c Y-Ba-Cu-O Films by Three-Target Magnetron Sputtering

The mechanism of deviation in the composition of sputtered films from the target was studied using a three-target magnetron sputtering system. Films were prepared in two different deposition geometries: first, the three targets were facing the substrate, and second, they were turned far away from the substrate. A significant difference was observed in the gas pressure dependence of film composition between these two geometries. The difference was attributed to the difference in bombardment probability of the films by high-energy O 2- ions. The T c of the film deposited with no ion bombardment effect was 84 K.