Effect of diffusion length on the nucleation of chemical vapour deposition diamond

Atomic steps have been suggested as preferential sites for nucleation. However, evidence from recent experiments on diamond growth using faceted sapphire as well as reconstructed silicon substrates shows that atomic steps alone do not always enhance nucleation in the chemical vapour deposition environment. The comparison of the diffusion length of the nucleation precursors and the width of the terraces between the surface steps provides further insights into this nucleation mechanism.