Infrared optical constants and dielectric response functions of silicon nitride and oxynitride films

The complex refractive indices of thick plasma-enhanced chemical vapour dep osited silicon nitride and oxynitride films were determined within the infr ared spectral region (4000-400 cm(-1) i.e. 2.5-25 mum) and used further to obtain their complex dielectric response functions. The imaginary part, i.e . the so-called energy-loss-function was analysed to get accurate phonon da ta of the amorphous layer. This way, TO-phonon frequencies, half-widths, an d intensities of characteristic infrared absorptions were determined for ea ch film. The dependence of the obtained data upon the variation of chemical /physical structure of the amorphous lattice was discussed.