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The present study deals with the interaction of C-terminated c(2×2) and Si-rich 3×2 3C-SiC (100) reconstructed surfaces with a microwave plasma chemical vapor deposition used for diamond growth. Pure hydrogen and hydrogen/methane exposures have been carried out. Their effects on the atomic ordering and the stoichiometry within the first planes have been studied in situ using low energy electron diffraction and electron spectroscopies: x-ray photoelectron spectroscopy, x-ray Auger electron spectroscopy, and ultraviolet photoelectron spectroscopy. 5min plasma exposures result in a lost of the initial reconstructions, a postplasma oxygen contamination, and strong modifications of the stoichiometry within the first planes. Indeed, the stability of well defined 3C-SiC surfaces depends strongly on their termination: C-terminated surface exhibits a high inertia while the Si-rich surface undergoes partial etching. The three first silicon atomic planes involved in the 3×2 reconstruction are removed upon pure hydrogen plasma while a monolayer is preserved after hydrogen/methane exposure.

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of thin and smooth nanocrystalline diamond films requires a high degree of control of the nucleation stage. The nature of the interface between diamond film and substrate is also important for some applications. The successive steps of the bias-enhanced nucleation (BEN) process are studied in-situ on Si(100) and 3C-SiC(100) using electron spectroscopies. Thin nanodiamond films (80-900 nm) have been achieved on Si(100). The formation of a thin covering SiC layer (2-3 nm) during the plasma exposure for parameters stabilization (PEPS) step leads us to study the plasma/surface interactions on 3C-SiC(100) surfaces. The C-terminated 3C-SiC(100) demonstrates a large inertia under microwave plasma (MP)CVD conditions. An enhancement of diamond nucleation on this surface is observed. Moreover, surface analysis reveals very little damage after BEN on 3C-SiC surfaces.