Formation and properties of copper film on Tl-(Pb, Bi)-Sr-Ca-Cu-O superconductor by electrodeposition from aqueous solution

Abstract

A new process of electrodeposition in saturated cupric sulphate aqueous solution was successfully developed for the formation of copper film on a high-T_c, three Cu-O layered Tl-(Bi, Pb)-Sr-Ca-Cu-O superconductor substrate surface for the first time. Scanning electron microscopy and electron micro-probe analysis were used to investigate the morphology of the substrate surface and the composition of the copper superconductor interface. After the electrodeposition process, no evident changes in the temperature dependence of electrical resistivity were found by four-point probe measurement. The difference of magnetic properties before and after electrodeposition was investigated from magnetization measurements. Almost no degradation of the bulk properties was observed from the susceptibility data. The copper-superconductor contact was confirmed to show Ohmic behaviour by two-pointI–V characterization at liquid nitrogen boiling temperature.