Theoretical and experimental studies of the atomic structure of oxygen-rich amorphous silicon oxynitride films

In this work we used an empirical potential model in order to describe the bulk structure of the oxygen-rich Si-O-N amorphous system. From the atomic configuration obtained by Monte Carlo simulations, the local order structure and the pair correlation function are determined. The results show that the basic structure of the amorphous is well described by a random distribution of tetrahedra with a central Si atom bonded to nitrogen and oxygen atoms. The Fourier transform of the extended x-ray-absorption fine structure (EXAFS) signal obtained by ab initio multiple-scattering calculations, using the theoretical atomic structure as input, shows good agreement with the experimental EXAFS analysis performed at the silicon K edge.