Deposition Coated Conductor Buffer Layers Films By Magnetron Sputter Method

Owing to its excellent electrical properties, YBa₂Cu₃O_x (YBCO) thin films has been regarded by the groups from science to industry abroadly. The main problem in fabricating coated conductor are lattice mismatch and the diffusion of oxygen and metal atom. A buffer layers is necessary to prevent Ni diffusing and provide a template for the subsequent growth of the YBCO superconducting layer.In this thesis,we prepared the films maily from magnetron sputter. First, discussed the possibility of depositing YBiO₃ films by magnetron sputter,analysed synthesize and pressing of ceremic targets;then researched the process of perparing buffer layers CeO₂ and solved the problem of substrate oxygenation.Finally,achieved epitaxial textured films.The major contents as follows:1. Significant scientific as well as practical interests of the coated conductor research have been introduced;2. The principle,classity and applications of magnetron sputter deposition,in this thesis,we adopted DC sputtering mostly;3. Thermal analysis ( TG-DTA ) was adopted to character the powders heating process. The phase structure and fractured surface morphology characteristics for the corresponding bulks and films were studied by XRD and SEM, Moreover, the smooth and epitaxial textured YBiO₃ film on the single crystal silicon substrate were prepared using the YBiO₃ targets synthesized from these two kind methods(precipi-tation method and solid state reaction method);4. Deposited the smooth and epitaxial textured CeO₂ films on Ni-W tapes by two-steps,avoiding the substarte oxygenation.First,pre-deposition a layer of Ce films to protect the substrate;then deposited CeO₂ films in the atmosphere of oxygen and argon.Therefore,we researched the influences on structures and surface morphology of films by atmosphere(the ratio between oxygen and argon ),substrate temperature and sputter power in the react DC sputtering systemly.