Ti/TiN multilayers for hard coatings applications: in-situ characterization by real time spectroscopic ellipsometry
Résumé
Single Ti and TiN, thick films and Ti/TiN, multilayers have been deposited by reactive rf-sputtering with in-situ control by spectroscopic ellipsometry. Spectroscopic ellipsometry allows one to measure precisely in real time the thickness of the deposited layers after calibration of the optical indices of the materials. For multilayer deposition, the interdiffused layers can be followed in-situ and the interdiffusion mechanism can be understood. In this way, we have found that the interfaces of this system deposited by rf-sputtering are asymmetric. Different multilayer samples have been realized by varying the thickness of each component from l-10 nm with the same total thickness of stack (200 nm). Sliding wear tests were made to evaluate the wear lifetime of the samples and to compare the results with those on simple thick films.