Single Phase a-axis YBCO Films Epitaxially Grown on NdGaO3

YBa2Cu3O7−x (YBCO) thin films on NdGaO3 (110) have been prepared using a newly developed DC-94.92MHz hybrid plasma magnetron sputtering. The hybrid plasma was generated by applying a negative bias voltage to the RF cathode. The YBCO films showed an excellent crystallinity with the a-axis being perpendicular to the plane of the substrate. A full width at half maximum (FWHM) value of 0.027° in the rocking curve through the (200) peak and χmin of 3.8% in the Rutherford backscattering channeling measurement were achieved. The interface between the film and the substrate was found to be very sharp by cross-sectional transmission electron microscopy (TEM). The surface of the films were also very smooth.