Analyses of diamond nucleation processes on carbonized substrates

The formation of carbonized interface layers is a spontaneous stage in the nucleation process of the chemical vapor deposition (CVD) of diamond onto substrates, however, the relationship between the carbonization and nucleation stages has not been well understood to date. This paper will discuss diamond nucleation mechanisms in relation to the carbonization of silicon substrates. For this purpose the silicon substrates are first carbonized using direct resistive heating. Then, diamonds are deposited on the substrates using a hot-filament CVD (HF-CVD) method. The experimental results reveal that when no ion effects exist, the solid-phase carbon reaches the same thermal equilibrium state as in the gas-phase during diamond deposition, and that the formation of the carbonized interface layers has no immediate relationship to diamond nucleation.