Preparation and Properties of Ultrathin High-Tc Superconducting Films on Si

Abstract

Ultrathin Ba₂YCu₃O _x films with thickness down to 7 nm were grown epitaxially on a Si(100) substrate using buffer layers (Y₂O₃(10 nm) and YSZ(40 nm)). These films show metallic behavior and full superconductivity through revealing broadened transitions. The critical current densities at 40 K are about 5×10⁶ A/cm² and 5×10⁵ A/cm² for 100 nm- and 28 nm-thick films, respectively.