Deposition of Si, Ge and C atoms onto a Si (001) substrate at various temperatures was investigated. Diffusion and arrangements of adatoms at various temperatures were observed. At 900K, the deposited atoms were more likely to form dimers in the perpendicular [110] direction due to the more favourable movement along the perpendicular [110] direction. Carbon adatoms were more likely to break or reconstruct the dimers on the substrate surface and had larger diffusion distances than did Ge or Si adatoms. Exchanges between C adatoms and substrate atoms were obvious, and the epitaxial thickness was small. When a newly arrived adatom reached the stable position, the potential energy of the system decreased and the curves took on a ladder-like shape.

Surface Diffusion of Si, Ge and C Adatoms on Si (001) Substrate Studied by the Molecular Dynamics Simulation. Chen, Z.H., Yu, Z.Y., Lu, P.F., Liu, Y.M.: Chinese Physics B, 2009, 18[10], 4591-7