Formation and orientation control of Y2O3 inclusions in pulsed laser deposited YBa2Cu3O7−δ films by using a melt-textured target

The formation and orientation of Y2O3 inclusions in pulsed laser deposited YBa2Cu3O7−δ films by using Y2BaCuO5-containing melt-textured target have been studied by X-ray diffractometry and transmission electron microscopy. The results show that Y2O3 inclusions, rather than the Y2BaCuO5 phase contained in the target, are formed in the films. [111]- and [100]-oriented Y2O3 inclusions have been found in the YBa2Cu3O7−δ films. The orientation of Y2O3 inclusions is dependent on the deposition temperature. If the deposition temperature is high enough, [111]-oriented Y2O3 can be inhibited. The reasons for the formation of Y2O3 inclusions and their orientation are discussed.