Title :
Superconducting properties of Tl-Ba-Ca-Cu-O films on silver substrates
Author :
Dye, R.C. ; Arendt, P.N. ; Martin, J.A. ; Hubbard, K.M. ; Elliott, N. ; Reeves, G.
Author_Institution :
Los Alamos Nat. Lab., NM, USA
fDate :
3/1/1991 12:00:00 AM
Abstract :
Films of Ba-Ca-Cu-O have been RF-magnetron-sputtered onto Consil 995 substrates. A postdeposition anneal in an overpressure of Tl produces the superconducting 1212 and 2212 phases. Varying the annealing procedures changes the electrical properties of the final films dramatically. Dynamic impedance, a novel approach to the electrical characterization of these films on a conductive substrate, is discussed and compared with SEM (scanning electron microscope), XRD (X-ray diffraction) and RBS (Rutherford backscattering) measurements as a function of differing annealing protocols. The improvement in the superconducting responses as a function of annealing procedures correlates well with the improved morphology observed in the SEM photographs. Also, the XRD data show increased c-axis material with the C annealing protocol
Keywords :
Rutherford backscattering; X-ray diffraction examination of materials; annealing; barium compounds; calcium compounds; high-temperature superconductors; scanning electron microscope examination of materials; sputtered coatings; superconducting thin films; superconducting transition temperature; thallium compounds; Consil 995 substrates; RF-magnetron-sputtered; Rutherford backscattering; SEM; Tl-Ba-Ca-Cu-O films; X-ray diffraction; c-axis material; electrical properties; high temperature superconductor; impedance; postdeposition anneal; Annealing; Backscatter; Conductive films; Impedance; Protocols; Scanning electron microscopy; Silver; Superconducting films; X-ray diffraction; X-ray scattering;
Journal_Title :
Magnetics, IEEE Transactions on
