Nb3Al thin-film synthesis by electron-beam coevaporation

Abstract

[[abstract]]Nb3Al thin films have been prepared and characterized with varying deposition parameters, including substrate temperature, deposition rate, gas doping, and epitaxial growth. Nb‐Al samples made with the optimum substrate temperature have lattice constants following the prediction of Geller radii and a systematic Tc increment with Al composition, namely, a ΔTc/ΔC of 1.9 K/at% Al. Employment of the self‐epitaxial method results in extending the A15 phase boundary by 1 at% Al and an enhancement of Tc by 2.4 K at a given substrate temperature. By extrapolating from Tc =16.7 K, the highest transition temperature observed in this work, stoichiometric Nb3Al is predicted to have an Tc onset of 20.7 K.[[fileno]]2010113010030[[department]]物理