Elastic and vibrational properties of nickel films measured by surface Brillouin scattering

Abstract

Surface Brillouin scattering has been used to measure the dispersion relations of surface, interface, and guided modes in nickel films supported on quartz glass with thicknesses of 100, 200, 500, 1000, and 2000 nm. The elastic constants of nickel have been estimated near the glass interface and near the free surface of the film. Thin films (up to 500 nm) turn out to be homogeneous, while thicker films show increasingly higher values of the elastic constant c₄₄. This behavior could be related to a change from the (111) preferentially oriented nickel crystallites on the glass, typical of thin FCC films, to a more isotropic growth for thicknesses greater than about 500 nm.