Microstructure study of YBa2Cu3O7-? thin film withsynchrotron-based three-dimensionalreciprocal space mapping br

High-temperature superconducting films can be used for fabricating the cutting-edge high-temperaturesuperconducting microwave devices because of their low microwave surface resistances. However, the microwavesurface resistances of high-temperature superconducting materials are particularly sensitive to microstructuredue to their special two-dimensional superconducting mechanisms and extremely short superconductingcoherence lengths. To investigate the correlations between microstructure and microwave surface resistance ofhigh-temperature superconducting materials, YBa2Cu3O7-d (YBCO) films with different thickness are grown on(00l)-oriented MgO single-crystal substrates by using the pulsed laser deposition (PLD) technique. Electricalmeasurements reveal that their superconducting transition temperatures and room temperature resistances donot show significant difference. However, their microwave surface resistances in superconducting state display asignificant difference. The characterizations of the microstructures of YBCO films by synchrotron radiationthree-dimensional reciprocal space mapping(3D-RSM) technique show that the number of the grains with CuO2face parallel to the surface (c crystals), and the consistency of grain orientation are the main causes for thedifference in microwave surface resistance