IN-SITU-PREPARATION, CHARACTERIZATION AND TRANSPORT-PROPERTIES OF HIGH-QUALITY BI2SR2CACU2OY-THIN FILMS

We report the preparation of Bi2Sr2CaCu2Oy-thin films with inductively measured T(c)-values of up to 92 K by dc-sputtering from a single sto ichiometric target in pure oxygen atmosphere. The excellent structural properties of these films are revealed by X-ray diffraction in Bragg- Brentano-geometry, PHI-Scans and RBS. In detail we present measurement s of the resistive transitions in magnetic fields up to 10 T, the depi nning-line and the field-dependence of the activation energy. Measurem ents of the critical current density (j(c)(70 K) = 10(6) A/cm2) exhibi t a comparatively slow decline of j(c) with increasing magnetic field. The angular dependences of j(c) and of the magnetoresistance in exter nal fields confirm the two dimensional behavior of the 2212-compound, in the latter case even up to 4 K above T(c). Furthermore we found a c lear correlation between the critical temperature of the films and the ir carrier density and mobility.