Low-temperature deposition of Y-Ba-Cu-O films on a CaF2/GaAs substrate

Abstract
Superconducting thin films of Y‐Ba‐Cu‐O were fabricated on a CaF2/GaAs(100) substrate using the rf planar magnetron sputtering technique. Substrates were heated as low as 450 °C during deposition. The as‐deposited films without high‐temperature post‐annealing have a transition temperature of 75 K and zero resistance temperature of 45 K. The perovskite structure usually observed in this system was not observed. The critical current (Jc) value of 2×103 A/cm2 was measured at 4.2 K.