Hetero interfaces of Bi-based superconductorrinsulator and electrical properties

A thick film of the Bi-based superconductor was fabricated onto the oxide polycrystalline substrates such as MgO, ZrO2 and SrTiO3 where system will be a new composite. The thickness was about 10 mm. The lowest electrical resistivity of 11 mV cm at 110 K for the isostatic pressed system of the superconductorrMgO, and 10 mV cm at 110 K for the SrTiO3 substrate. The large grain size at the surfaces was found to be important as well as the dense surfaces. No changes of the critical temperature were found on any substrate. The interfaces between the film and the substrate can be controlled by the pressing process which is important to reduce the electrical resistivity. q1998 Elsevier Science B.V. All rights reserved