DEPOSITION OF MOLYBDENUM NITRIDE THIN-FILMS BY RF REACTIVE MAGNETRON SPUTTERING

Molybdenum nitride thin films were prepared by the reactive r.f. magne tron sputtering technique, on grounded substrates, using nitrogen as r eactive gas. The effect of the variation of nitrogen partial pressure and the substrate temperature on the microstructure of these films has been investigated. X-ray and electron diffraction studies were used t o optimize the growth conditions leading to single-phase gamma-Mo2N th in films. The composition of the films was estimated using Auger elect ron spectroscopy studies. Single-phase f.c.c. gamma-Mo2N films exhibit ing metallic conductivity have been obtained over a wide range of nitr ogen partial pressure. The films were polycrystalline in nature having grain size in the range 10-25 nm. The preferred orientation of the cr ystallites and the lattice parameter are found to depend on the nitrog en incorporation in the film. The morphology of all the films lies in the zone T regime of Thornton's structure zone model. The resistivity of these films exhibits a dependence on the size and orientation of th e grains and appears to be determined by grain-boundary-related effect s. The microstructure of the films is not significantly influenced by a variation of the substrate temperature in the range 300-575 K.