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.