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

Abstract

The complex refractive indices of thick plasma-enhanced chemical vapour deposited silicon nitride and oxynitride films were determined within the infrared spectral region (4000-400 cm-1, i.e. 2.5-25 μm) 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 data of the amorphous layer. This way, TO-phonon frequencies, half-widths, and intensities of characteristic infrared absorptions were determined for each film. The dependence of the obtained data upon the variation of chemical/physical structure of the amorphous lattice was discussed.