The nature of ripples and islands in strained SiGe/Si heteroepitaxy: nucleation vs. instability phenomena

摘要

Using liquid phase epitaxy from Bi solution in the temperature range 550 deg C - 700 deg C at low growth rates we study the formation of ripples and islands and their interdependence. As main results we find from the dependencies on growth time and temperature that ripples are an instability phenomenon and that islands nucleate thermally activated. Island nucleation on a ripple template (that is, as an instability phenomenon, highly ordered) has huge impact on the achievable order of the islands.