Surfactant-mediated growth of germanium on silicon (001) with submonolayer coverage of Sb and Te

Surfactant-mediated growth of germanium on silicon (001) with submonolayer coverages of antimony and tellurium, respectively, was investigated with reflection high-energy electron diffraction and transmission electron microscopy. Approximately 0.2 monolayer of antimony is needed for a complete suppression of islanding for the growth at 450 °C. For growth at a lower temperature (270 °C), only approximately 10% of a monolayer antimony or tellurium is needed in order to obtain smooth epitaxial germanium layers. No differences could be detected between tellurium and antimony in the behavior as a surfactant. The performed surfactant-mediated growth experiments can be understood as the kinetic suppression of islanding due to a reduction in surface diffusion of germanium adatoms.