Defect-induced Si/Ge intermixing on the Ge/Si(100) surface

Si/Ge interfacial intermixing phenomena have often been observed in epitaxial Ge overlayer growth on Si surfaces. Yet, it is not clear if this Si/Ge intermixing originates from an energetically favorable configuration or from nonequilibrium growth conditions. Using the first-principles calculations we propose a model of defect-induced Si/Ge intermixing that is both energetically and kinetically favorable. We further discuss the intermixing phenomena at stepped Si surfaces.