Elaboration and characterization of Ti and TiN thin films and Ti/TiN multilayers for hard coating applications

In this paper, we report on the growth of titanium and titanium nitride thin films and of Ti/TiN nanometric multilayers. The elaboration of these films has been carried out by high-vacuum diode r.f, sputtering. The growth was monitored in-situ by kinetic ellipsometry. The film thickness ranged from 50 to 200 nm for the Ti and TiN single layers. For the multilayers, the thickness of each component was varied from 1 nm to 10 nm and alternately repeated in order to obtain a total thickness of 200 nm. After deposition, the films were characterised by means of X-ray diffraction, grazing incidence X-ray reflectometry, atomic force microscopy and transmission electron microscopy for structural determination. A comparison is made between the microstructural and the mechanical properties of Ti and TiN films on the one hand and the multilayers on the other hand (porosity, density and so on). We show that the wear properties are increased by multilayering.