As-grown thin MgB2 films were deposited, by pulsed laser deposition, onto MgO and Al2O3 substrates. Starting with a non-stoichiometric, Mg and B mixed-powder, target it was possible to grow the superconducting phase during film deposition, without further annealing. Samples grown at 400 to 450C under an Ar buffer pressure of about 10-2mbar were superconducting, with an onset temperature of the resistive transition at about 25K. It was demonstrated that this method permitted the in situ deposition of as-grown superconducting thin films.

As-Grown Magnesium Diboride Superconducting Thin Films Deposited by Pulsed Laser Deposition. G.Grassano, W.Ramadan, V.Ferrando, E.Bellingeri, D.Marré, C.Ferdeghini, G.Grasso, M.Putti, P.Manfrinetti, A.Palenzona, A.Chincarini: Superconductor Science and Technology, 2001, 14, 762-4