Abstract
Thick oxide films (≈220 nm) have been nitrided heavily in ammonia. Dispersion analysis was performed on infrared transmission spectra of oxide, nitrided oxide, and CVD nitride films. The following conclusions may be drawn from the spectra: nitrided oxide is not the same material as CVD silicon nitride; nitridation results in significant loss of Si‐O asymmetric stretch intensity; and nitridation leads to the appearance of a spectral peak for planar triply bonded N‐Si asymmetric stretch analogous to that in trisilylamine. About 43% of the oxygen was replaced by nitrogen.