Off-axis laser deposition of YBa2Cu3O7−δ thin films

Abstract

We report on YBa₂Cu₃O_7−δ thin‐film preparation by a new laser deposition geometry, the so‐called off‐axis laser deposition. Combined with radiation‐based substrate heating, this results in c‐axis oriented, epitaxial YBa₂Cu₃O_7−δ thin films with critical current densities above 10⁶ A/cm² at 77 K and zero field and an exceptionally good surface quality, with complete absence of the otherwise observed laser droplets. As proved by atomic force microscopy, the surface roughness is 2. Using this off‐axis geometry it is possible to coat both sides of a substrate simultaneously, providing a one‐step process in double‐sided thin‐film deposition. Both YBa₂Cu₃O_7−δ films on the substrate show identical superconducting properties.