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As devices get smaller, a challenge is presented to those who determine the physical properties of the materials used within these devices in a fast and reliable way. This thesis attempts to answer, in part, to that challenge, with a focus on the elastic and, to a lesser extent, thermal properties of thin functional filmsthat are deposited on single crystal substrates. The elastic anisotropy introduced by the single crystal substrate has a major effect on the surface acoustic wave (SAW) velocity and its dispersion. The aim of this work is to extract the elastic properties of functional coatings, and exploit the anisotropy of the substrate, through the fitting of the SAW velocity dispersion. This approach brings an addition to earlier work at ATF (KU Leuven), the Applied optics group (University of Nottingham) and the Keith Nelson research group (MIT). Experimentally the SAW velocity dispersion is measured through two all optical methods. Impulsive stimulated thermal scattering (ISTS, also known as heterodyne diffraction or transient grating) and grating induced laser beam deflection (GILBD) both excite and detect SAWs, with a chosen wavelength, on reflective surfaces. Several films were investigated, each presenting the applicability of the presented approach toother situations. Nanocrystalline diamond (NCD) attempts to bring the extraordinary properties of diamond to applications. In this thesis the elastic and thermal properties were determined, and were found to be in line with literature values. It also reveals that this technique is able to characterize a rough isotropic intermediate layer (a Cr top coating was deposited to enhance reflectivity). Sintered porous …