Microwave surface resistance of YBCO thin films on cerium oxide buffer

A study on how the microwave surface resistance of YBa2u3Oy (YBCO) thin films are affected by the crystallinity and surface roughness of CeO2 buffer on R-plane Al2O3 substrate was conducted. X-ray diffraction method was used to measure the microwave surface resistance from the microstrip line resonator's transmission characteristics. Results show that the quality of the upper layer of the YBCO is affected by the poor crystallinity of thin CeO2.