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In this thesis, the development of superconducting materials, applications, and classification; the of REBa 2 Cu 3 O 7-x (RE behalf of rare earth elements) development and preparation of superconducting thin films of high-temperature superconducting tapes; the of REBa 2 Cu 3 O 7-x high-temperature superconducting materials using elements of alternative methods to improve the critical current. Then, the paper uses a fluorine-free metal organic deposition (MOD) in the the the monocrystalline substrate LaAlO 3 (100) the prepared DyBa 2 Cu 3 O 7-x (DyBCO) film. The first experiment to determine the best epitaxial growth temperature zone of 770 ℃, then the introduction of a certain amount of water vapor in the atmosphere to analyze the impact of film growth. Experimental results show that the introduction of water vapor is not conducive to the growth of the film, and finally by the partial melting method DySCO further optimize the epitaxial growth process. The samples subjected to X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) analysis, and the superconducting properties of the test, obtained good DyBCO film the c-axis texture, smooth and dense surface, the critical superconducting transition temperature of 92K, 77K under self-field The critical current density of approximately 1.5MA/cm 2 . Finally, doped YBCO Cu sites. Broader YBCO application YBCO doping research more practical significance, and process of DyBCO can be directly transferred to the of YBCO, a result of YBa the 2Cu the (3-x) M x O 7 - y (M = Zn, Ni, Fe) of the Cu bit doping of, X = 0.0005,0.001,0.005. By X-ray diffraction (XRD), scanning electron microscopy (SEM) and the superconducting properties of the test to analyze the doping of YBCO impact. Ni, Zn, Fe, trace doping after YBCO thin film having a good c-axis texture, while the morphology of the film can be improved. Ni, Zn, Fe doping will inhibit superconductivity, as the doping amount increases, the superconducting transition temperature is reduced, from strongest to weakest is: Zn, Ni, Fe,. Ni, Zn, Fe, the dopant would be introduced pinning centers, the film from the flux pinning role. Different elements at different temperatures flux pinning effect is different. Ni Zn doping amount 0.001 at 77K showed the best flux pinning effect, the the pinning effect gradually weakened as the temperature drops; 77K, 65K 0.0005 doping amount pinning the strongest, 50K, 30K The strongest effect of the doping amount of the pinning, 10K 0.001; are strong pinning effect of the the Fe doping amount of 0.0005 in the entire temperature range, the temperature dropped to 50K, 0.001 doping amount under high field gradually to show a higher pinning effect.
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