Investigation of Precursors Formed by Mixing SiH₂Cl₂ with NH₃ for Chemical Vapor Deposition of Silicon nitride Films

Precursors for Silicon nitride films prepared by mixing SiH 2 Cl 2 with NH 3 were investigated by in situ Fourier-transform infrared spectroscopy (FT-IR) and mass spectrometry. The FT-IR spectral analysis results indicated that the Cl was removed from SiH 2 Cl 2 by mixing SiH 2 Cl 2 with NH 3 at room temperature (R.T.). The analysis results also indicated the existence of radicals which had the chemical bond Si–N. The mass spectral analysis results indicated the existence of the radicals with the mass number of 45–47. From these results, it was concluded that the precursors of SiNH x for SiN films were formed by mixing SiH 2 Cl 2 with NH 3 .