Superconductivity of MgB2 sputtered thin films with aluminium nitride buffer layers

• Published in: Physica. C, Superconductivity Superconductivity, 2007-09, Vol.460-462 (1), p.557-559
• Main Authors: Ilonca, G., Yang, T.R., Pop, A.V., Toma, V., Balint, P., Bodea, M., Marconi, D., Jurcut, T.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Critical currents; Exact sciences and technology; Hall effect; High-tc films; Magnetization; Magnetotransport properties; Physics; Properties of type I and type II superconductors; Superconducting films and low-dimensional structures; Superconductivity; Thin films
• ISSN: 0921-4534; 1873-2143
• DOI: 10.1016/j.physc.2007.03.251

MgB2 thin films were deposited, at low temperature substrates, in situ, on a polished c-cut sapphire substrates, with the aluminium nitride (AlN) buffer layers, using the multiple-target sputtering system. The magnetoresistivities were measured using dc–4 terminal method in applied magnetic field up to 9Tesla. The upper critical field anisotropy, Hc2(T) and irreversibility field Hirr(T) versus temperature were determinated. The Hall density of charge are slightly temperature dependence and positive in normal state. The critical temperature of 30–32K and critical current density of 106–107A/cm2 at 4, 2K were obtained. Using extracted data, the coherence length ξ0, anisotropic coefficient γ and penetration depth λL were calculated.