I n s i t u growth of YBa2Cu3O7−x high T c superconducting thin films directly on sapphire by plasma-enhanced metalorganic chemical vapor deposition

Abstract

Highly c‐axis oriented YBa₂Cu₃O_7−x superconducting thin films have been, in situ, deposited directly on sapphire substrate by a remote microwave plasma‐enhanced metalorganic chemical vapor deposition process (PE‐MOCVD). The films were deposited at a substrate temperature of 730 °C followed by a fast cooling. The as‐deposited films show attainment of zero resistance at 82 K and have critical current density of 10⁴ A/cm² at 70 K. ac susceptibility measurement indicated that the films contain a single superconducting phase. PE‐MOCVD was carried out in a commercial‐scale MOCVD reactor with capability of uniform deposition over 100 cm² per growth run.