The characterization of thermal cycling behavior of YBa/sub 2/Cu/sub 3/O/sub 7/ on Y-stabilized ZrO/sub 2/ buffered [100] Si

The thermal cyclic behavior of the YBa/sub 2/Cu/sub 3/O/sub 7/ high-temperature superconductor (HTS) thin film on Y-stabilized ZrO/sub 2/ buffered [100] Si was systematically studied in this paper. These HTS assemblies underwent thermal cycling from 77 K to room temperature, and their thermal fatigue reliability was evaluated by the initiation and propagation of their thermal fatigue defects by using the SEM measurement, It was found that YBa/sub 2/Cu/sub 3/O7 superconductor thin films on the Y-stabilized ZrO/sub 2/ buffered [100] Si substrate eventually spalled after a number of cycles under temperature fluctuation. It is noticed that the processing parameter and procedures of the superconductor assemblies plays an important role on the cyclic life of the assembly. It is noticed that the defects in the buffer layer, inhomogeneity of the film composition and cluster size, and variation in film thickness not only enhance the defect initiation, but also have a significant influence on the superconductivity of the superconductor assemblies. The results of this study provide some practical information with regard to the performance enhancement and quality control of these thin-film superconductor devices,.