Residual stress gradient of Cr and CrN thin films

In this work Cr, CrN thin films were grown by the Magnetron Sputtering technique on monocrystalline silicon (400) substrates. Also, a (Cr/CrN)₂ multilayer film was grown in order to compare the values of stress between multilayer and single layers. The total thickness of all films was approximately equal to 1 μm. Structural characterization and residual stress measurements were performed by the grazing X-ray diffraction method and the data were collected at LNLS - Brazilian Synchrotron Light Laboratory. Different angles of incidence were selected in order to obtain values of residual stress at different penetration depths. A linear model of residual stress as a function of the depth profile from experimental data was obtained by using the Laplace transform. Results indicate smaller tensile residual stress at surface and higher stresses at film/substrate interface for the Cr monolayer and for the CrN phase in the (Cr/CrN)₂ multilayer. On the contrary, the CrN film presented higher tensile stresses at surface.