Magnetic penetration depths in superconducting NbN films prepared by reactive dc magnetron sputtering

Abstract

Penetration depth λ behavior in reactively sputtered NbN films has been examined. For NbN films deposited at 300 °C or higher by means of dc magnetron technique, λ values around 300 nm were obtained, very short compared with the previously reported values (500–700 nm). The measured λ dependences on deposition parameters are discussed in connection with film structure on the basis of the Ginzburg–Landau–Abrikosov–Gor’kov theory of type II superconductivity.