Local nucleation of diamond heteroepitaxy on Si(100) in the initial stage and the role of atomic hydrogen

The reaction of atomic hydrogen with a C2H2-covered Si surface was studied using high-resolution electron-energy-loss spectroscopy, low-energy electron diffraction and Auger electron spectroscopy. The findings were that atomic hydrogen broke up the C–C bond in C2H2 and the Si–Si dimer to form C–H and Si–H, respectively. In terms of experimental phenomena, a cluster model for quantum chemistry calculations was devised. The results agreed well with experiment; the role of atomic hydrogen and the nucleation mechanism of diamond heteroepitaxy on Si were discussed.