Correlations among structural, transport, and microwave properties of YBCO thin film on LaAlO3 substrate by chemical vapor deposition

Abstract The microstructure and microwave performance of eight YBa 2 Cu 3 O 7−δ (YBCO) thin films grown on LaAlO 3 substrates by chemical vapor deposition have been studied. The lowest surface resistance at 10 GHz and 77 K was calculated to be 1.2 mΩ from the unloaded quality factor of a 5.6 GHz resonator. With one exception the quality factor of resonators made from these films was proportional to the DC critical current density. This correlation has previously been observed for YBCO films grown on LaAlO 3 by laser ablation. The microwave performance of these films does not correlate well with their structure properties due to the presence of a large amount of secondary phases and a -axis oriented grains.