Fabrication of superconducting magnesium diboride thin films by electron beam annealing
Abstract:The technique of electron beam annealing for fabricating MgB2 thin films has been explored. MgB2 thin films were prepared by e-beam evaporation of M–B precursor films on 6H–SiC (0001) substrates followed by ex situ electron beam annealing without any extra Mg vapor or argon gas protection. The very short annealing duration, about 1 s, effectively prevented volatilization and oxidation of Mg and decomposition of MgB2. In comparison with the MgB2 thin films grown by other techniques, our films show medium qualities including a superconducting transition temperature of T c onset ~ 35.3 K, a transition width ΔT c ~ 0.2 K, and a critical current density of J c(5 K, 0 T) ~ 3.2 × 106 A cm − 2. Such an electron beam annealing technique has potential for the fabrication of large-scale MgB2 thin films as well as MgB2 wires and tapes.
Document Type: Research Article
Publication date: October 1, 2011