Electrical properties of Y1Ba2Cu3Ox films grown by liquid phase epitaxy

Y₁Ba₂Cu₃O_x films were grown on MgO(100) substrates by liquid phase epitaxy and their structural and electrical properties were examined. From transmission electron microscopy (TEM) plan-view images, it was found that the films consisted of large grains whose misorientation angles were less than 1°. Although d.c. critical current density values decreased with increasing film thickness, even a 7 μm-thick film showed the value of 9×10⁵ A/cm² at 77 K. An rf first penetration field of the film is estimated to be 30 Oe at 10.8 GHz and 77 K, by using a microstrip line resonator with a resonant frequency of 10.8 GHz. The third-order intercept point of the resonator is at an input power of +43 dBm and output power of +30 dBm at 77 K. These results suggest that LPE grown Y₁Ba₂Cu₃O_x films have superior d.c. and rf electrical properties.