Rutherford Backscattering analysis of Bi-based superconducting films

The elemental composition, film thickness and concentration depth profiles of precursor and superconducting (Bi,Pb)-Sr- Ca-Cu-O films were studied by the Rutherford Backscattering Spectrometry (RBS) technique. The precursor films were deposited on MgO single-crystalline substrates from an aerosol at...

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Detalles Bibliográficos
Autores: R. Vargas, J.C. Cheang Wong, E. Díaz Valdés, A. Morales, M. Jergel
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:1999
País:México
Institución:Universidad Nacional Autónoma de México
Repositorio:Redalyc-UNAM
OAI Identifier:oai:redalyc.org:94200943
Acceso en línea:https://www.redalyc.org/articulo.oa?id=94200943
Access Level:acceso abierto
Palabra clave:Física, Astronomía y Matemáticas
Bi
Superconductors
spray pyrolysis
based thin films
Rutherford Backscattering
Descripción
Sumario:The elemental composition, film thickness and concentration depth profiles of precursor and superconducting (Bi,Pb)-Sr- Ca-Cu-O films were studied by the Rutherford Backscattering Spectrometry (RBS) technique. The precursor films were deposited on MgO single-crystalline substrates from an aerosol atomized ultrasonically from an aqueous nitrate solution. Precursor films, about 5 to 5.5 mm thick, were then annealed in air at temperatures ranging from 835ºC to 855ºC during 10 h. XRD studies revealed mainly the presence of the 2212 phase (for bulk Tc is about 85 K). Films annealed at temperatures Ta ³ 850ºC were superconducting with Tc in the range of 60 to 71 K, showing a double Tc onset at 85 K and 110 K. The RBS study of the Bi-profile of precursors showed a maximum content of Bi at a depth around 1 to 2 mm from the film surface. After the film annealing, the Bi content was found to be constant from the surface to about 1 mm depth, decreasing then its value towards the film-substrate interface