JOURNAL DE PHYSIQUE IV

Abstract. Elaboration of amorphous SiCPc: materials was performed using a conventional thermaly activated CVD at 1000-12003C from the '1MS-NH3-H2 system. 'I'he influence on the deposition rate and the composition was investigated using an experimental design by varq-ing: deposition temperature, pressure and hTb flow rate. A set of 16 samples SiCxNy with x!y ranged from 0.0.1. to 1.69 was prepared..4ccurate determination of the elemental compositon required EPM.4-U?)S and XPS and occasionally RBS analyses. The chemical bonding system was investigated by XPS and Raman spectroscopy. Comparisons between CVD prepared silicon carbide and nitride reference samples and the SiCxNy materials were achieved. It was concluded that for x.y < 0.15, Si-iK was predominant, whereas for x:y 2 0.86, the amorphous deposits mainly contain Si-N and Si-C, and additionally- carbon bonds includmg C-Si and C-C, and probably a rather low C-N contribution. Raman study shown that C-C bonding could be related to a carbon excess acting as a binder in-between the tetrahedral networks of Si-C and Si-X. The first results of EXELFS concerning a carbon poor deposit shown that Si has a first coordination shell similar to that of Si3N4. 1