Smooth growth fronts in Si/Ge heteroepitaxy by kinetic growth manipulation

A promising route for growing atomically flat Si on Ge(100) is described. T he key to this achievement is the control of growth kinetics on an atomic l evel. We have identified the cause for the development of rough growth fron ts: the descent of atoms across steps, a prerequisite fur prolonged layer-b y-layer growth, is strongly suppressed at double steps. The developedproced ure for smooth growth avoids the formation of these double steps. The appro ach can be applied at low temperature (<550 K) and thus inherently avoids i ll chemical definition of the interface due to intermixing. It is expected to be generally applicable for epitaxy of pure Si and Ge on both Ge(100) an d Si(100) substrates. [S0163-1829(98)03148-8].