Modeling of glancing incidence X-ray for depth profiling of thin layers

In this work, we present a method to obtain quantitative information about the thickness of thin, polycrystalline layers. This non-destructive method is based on Glancing-Incidence X-ray Diffraction (GIXRD) experiments at different incidence angles. At different incidence angles, information about phases lying at different depths is obtained. The diffracted X-ray intensities' dependence on the glancing angle was analyzed and compared with simulations performed by means of a simple optico-geometrical model taking into account the Fresnel coefficients, X-ray absorption, and the effective scattered volume. The depth profile of polycrystalline Au layers was evaluated to test the procedure. The results of the GIXRD and the simulations are in very good agreement with the thickness obtained by means of X-ray reflectivity (XRR) technique.