Microwave resonances with partially untwinned YBCO films near 10 GHz

Partially untwinned YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) films on twin-free NdGaO/sub 3/-substrates have been fabricated by off-axis sputtering. The ratio of the a- and b-axis DC resistances is on the same order as untwinned crystals. The film DC resistances values differ by less than a factor of two from those of untwinned crystals. The surface resistance in the a- and b-direction near 10 GHz has been measured with only one parallel plate resonator of rectangular area. The anisotropy ratio of the surface resistance at 4.2 K is on the order of 1.9. The b-axis surface resistance at 10 GHz and 4.2 K is about 25 mu Omega .<>