Growth and structural characterizations of nanostructured chromium-zirconium-nitride thin films for tribological applications

Abstract

Nanostructured Cr-Zr-N thin films were grown on Si(100) substrates in a mixture of Ar and N2 plasma. The nitrogen partial pressure was varied to produce and control the stoichiometric forms obtained. All the Cr-Zr-N films exhibited a nanostructure with an average grain size of less than 10 nm, as determined by X-ray diffractogram analysis, and were formed in the solid-solution. As the contents of nitrogen in the film increased, it lead to changes in the crystal texture and competitive growth. The maximum root mean square roughness was 7.87 nm at a 20% nitrogen partial pressure and the roughness tended to decrease as the grain size decreased. The nano-indentation showed that the films grown at a 20% nitrogen partial pressure and annealed at 700°C had the highest reduced modulus and hardness at 349.2 and 35.1 GPa, respectively. The mechanical properties of films can be improved by a post-annealing heat treatment. With respect to the electrical properties of these films, the sheet resistance, which is related to the defect level, tended to increase as the nitrogen partial pressure increased. © 2010 The Japan Institute of Metals.