LAYERED HETEROEPITAXIAL GROWTH OF GERMANIUM ON SI(015) OBSERVED BY SCANNING-TUNNELING-MICROSCOPY

Germanium growth on a Si(015) substrate was examined by scanning tunne ling microscopy (STM) on an atomic scale. The Ge deposition on a Si(00 1) substrate showed the Stranski-Krastanov growth mode, where the depo sited films grew layer-by-layer up to a few ML followed by three-dimen sional island growth with (015) facets. Thus the Ge films were deposit ed on the Si(015) substrate in this study. As expected, the deposited Ge layers exhibited the layered growth mode up to thicker than 10 ML a t a growth temperature of 400 degrees C. The surface and the step stru ctures, which seemed deeply related to the layered growth mechanism, w ere observed with STM and discussed in detail.