SICN AMORPHOUS MATERIALS CHEMICAL-VAPOR-DEPOSITED USING THE SI(CH3)(4)-NH3-H-2 SYSTEM

Elaboration of amorphous SiCN materials was performed using a conventi onal thermaly activated CVD at 1000-1200 degrees C from the TMS-NH3-H- 2 system. The influence on the deposition rate and the composition was investigated using an experimental design by varying deposition tempe rature, pressure and NH3 flow rate. A set of 16 samples SiCxNy with x/ y ranged from 0.04 to 1.69 was prepared. Accurate determination of the elemental compositon required EPMA-WDS and XPS and occasionally RBS a nalyses. The chemical bonding system am investigated by XPS and Raman spectroscopy. Comparisons between CVD prepared silicon carbide and nit ride reference samples and the SiCxNy materials were achieved. It was concluded that for x y < 0.15, Si-N was predominant, whereas for x y g reater than or equal to 0.86, the amorphous deposits mainly contain Si -N and Si-C, and additionally carbon bonds including C-Si and C-C, and probably a rather low C-N contribution. Raman study shown that C-C bo nding could be related to a carbon excess acting as a binder in-betwee n the tetrahedral networks of Si-C and Si-N. The first results of EXEL FS concerning a carbon poor deposit shown that Si has a first coordina tion shell similar to that of Si3N4.