Title :
Preparation and characterization of NdBa/sub 2/Cu/sub 3/O/sub y/ thin films
Author :
Tang, W.H. ; Gao, J.
Author_Institution :
Dept. of Phys., Hong Kong Univ., Hong Kong
fDate :
6/1/1999 12:00:00 AM
Abstract :
C-axis oriented epitaxial NdBa/sub 2/Cu/sub 3/O/sub y/ thin films on [100] SrTiO/sub 3/ substrates were prepared by off-axis rf sputtering. Thin films with T/sub c0/=90 K in a deviation of 0.5 K were prepared reproducibly under the optimal depositing conditions. A parabolic relation of T/sub c0/ to c-axis lattice parameter corresponding to a typical electronic phase diagram for high-T/sub c/ superconductors was observed, indicating an optimal oxygen content for the best superconductivity. The oxygen out-diffusion and thermal expansion of the films were studied by an in-situ high temperature x-ray diffraction.
Keywords :
X-ray diffraction; barium compounds; high-temperature superconductors; neodymium compounds; self-diffusion; sputter deposition; stoichiometry; superconducting epitaxial layers; superconducting transition temperature; thermal expansion; HTSC; NdBa/sub 2/Cu/sub 3/O; NdBa/sub 2/Cu/sub 3/O/sub y/ thin films; SrTiO/sub 3/; [100] SrTiO/sub 3/ substrates; c-axis lattice parameter; c-axis oriented epitaxial films; characterization; electronic phase diagram; high temperature x-ray diffraction; high-T/sub c/ superconductors; off-axis RF sputtering; optimal depositing conditions; optimal oxygen content; oxygen out-diffusion; parabolic relation; preparation; superconductivity; thermal expansion; Lattices; Sputtering; Substrates; Superconducting films; Superconducting transition temperature; Temperature dependence; Temperature measurement; Transistors; X-ray diffraction; X-ray scattering;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
