Superconducting Transition Temperatures of R. F. Sputtered NbN Films

Abstract
NbN films are examined with respect to their electrical and superconducting properties. The films are deposited by r.f. reactive sputtering technique under argon gas atmosphere added with nitrogen. The films obtained have a wide range of resistivities and transition temperatures depending upon the partial nitrogen pressure in the argon atmosphere and the substrate temperature at which the films were deposited. The maximum transition temperature obtained is 17.3°K, higher by 0.9°K than the highest one reported so far.