EFFECT OF OXYGEN-PRESSURE ON PROPERTIES OF BI-SR-CA-CU-O THIN-FILMS GROWN BY LASER DEPOSITION

We present the results of a study of the effect of oxygen pressure on the properties of Bi-Sr-Ca-Cu-O (BSCCO) thin films grown by laser ablation. Films of the same phase, which were deposited at different oxygen pressures, show quite different properties. Here, we define the phases of BSCCO films from their c-axis lattice constants calculated from the 2theta X-ray diffraction angle of the 002 peak. In-situ films deposited at high oxygen pressure (greater-than-or-equal-to 100 mTorr) show higher critical temperatures and critical current densities. However, by post annealing, transport properties of films deposited at low oxygen pressure (several 10 mTorr) are improved significantly. With respect to this difference, the results of X-ray diffraction and energy dispersive X-ray spectroscopy studies, and Hall effect measurements are discussed.