Dynamics of strained-layer epitaxy: Simulation of growth and annealing of GexSi1−x/Si systems

Abstract

We simulate the epitaxial growth and annealing of GexSi1−x alloys on a Si(001) substrate using a stochastic Monte Carlo technique. Our simulation indicates that: (i) the overgrowth is defect-free for x≤0.2, whereas defect formation is inevitable for x≥0.5; and (ii) initiation of phase segregation into Si and Ge(001) layers is obtained by means of solely surface diffusion effects during growth and annealing. These result from the kinetically more active nature of Ge atoms as compared to Si atoms, together with an effect arising from the compressive strain in the alloy layers.