GROWTH OF GE ON SI(100) AND SI(113) STUDIED BY STM

Scanning tunnelling microscopy (STM) has been used to study Stranski-Krastanow growth (two-dimensional layer + three-dimensional island growth) of evaporated Ge on Si(113) and Si(100) substrates. The transition from purely two-dimensional layer growth to the formation of three-dimensional inelastically relaxed islands was found to proceed through a number of intermediate stages of growth. We have interpreted the growth morphology of the different stages in terms of partial elastic relaxation of the overlayer strain. The stabilizing effect of the relaxation is correlated to the stress tensor of the reconstructed surface.