NUCLEATION AND GROWTH OF GERMANIUM ON SILICON (111)

The nucleation and growth of Ge on Si(111) substrates were investigated by transmission electron microscopy (TEM). It was found that growth is initiated by the formation of three-dimensional islands. At a very early stage of growth a polycrystalline layer was obtained. The orientation of this Ge film, however, improved as growth proceeded, resulting in an epitaxial film when the islands were fully coalesced. It was found that the major defects present in the Ge epilayer were microtwins (primary and secondary twins) occurring on the inclined {111} planes of Ge.