Early stages of the HFCVD process on multi-vicinal silicon surfaces studied by electron microscopy probes (SEM, TEM)

In this paper, we show that silicon dimples are suitable samples to study d iamond nucleation on a controlled distribution of defects by SEM FEG and HR TEM observations. Indeed, multi-vicinal surfaces generated by a UHV thermal treatment have been characterised by STM experiments. On these terraces, w e observed a strong increase of the nucleation density higher than two orde rs of magnitude compared to pristine silicon samples. Moreover, a preferent ial location of diamond nuclei along the steps is reported. This result is explained by the large surface diffusion length of carbon species compared to the terrace's width. Indeed, during the early stages of growth, oriented silicon carbide nano-crystals are observed with the relationship SiC(220)/ /Si(220). (C) 2001 Elsevier Science B.V. All rights reserved.