ACTIVATED STRAIN RELIEF OFGe/Si(100) ISLANDS

Stress concentration at the boundary of Ge/Si(100) islands drives strain relief mechanisms activated at higher growth temperature, T. Si interdiffusion for T≥ 550°C forms a reduced misfit alloy allowing specific cluster morphologies to exist at sizes greater than those for pure Ge islands. This interdiffusion also affects the pathway for island shape changes. Trenches formed at the island base result from diffusion of the most highly strained material to regions of lower strain and precede dislocation formation for T≥ 600°C.