Influence of Edge Energy on Modeling the Growth Kinetics of Quantum Dots

Recent experimental results suggest that the growth of elongated quantum dots with a rectangular base and quantum wires is possible under certain conditions in a germanium–silicon system. However, the role of formation of additional edges during the creation of such structures is still poorly researched. This paper evaluates the influence of the energy contribution from formation of additional edges in the change in free energy during quantum dot nucleation. A refinement has been carried out on the existing kinetic model of quantum dot formation and growth in the Stranski–Krastanow mode. In view of this contribution, the islands’ nucleation rate and surface density and the distribution function of quantum dots by size have been calculated. It is shown that taking the additional energy from the creation of edges into account is essential for obtaining more realistic estimates for the parameters of quantum dots arrays during numerical modeling of their growth.