Growth of 200angstroms Superconducting Bi-Sr-Ca-Cu Oxide Thin Films

Preferentially ^ above c axis oriented superconducting Bi-Sr-Ca-Cu oxide films as thin as 100angstroms have been successfully grown on MgO(100) substrates. Even though such thin films are only 6 - 7 unit cells thick, they still exhibit bulk superconducting properties. These films typically exhibit a superconducting transition temperature at 80K and a critical current density of 10 sup 5 A/cm sup 2 at 50K as determined by transport measurements. The ability to grow even thinner films is controlled by the exact film stoichiometry and the smoothness of the substrate surface.