Coherent growth of InAs/GaAs self-assembled quantum dots

An energetic balance between surface and elastic strain energies based in continuum elastic theory is applied to evaluate the transition thickness in InAs/GaAs (001) self-assembled quantum dots. The growth process follows a Stranski–Krastanov (S–K) pattern, where a two–three-dimensional transition is undertaken at the so-called transition thickness. The system under investigation is a pseudomorphological structure characterized by a coherent behavior at the substrate/film interface. For the dependence of the lattice parameter with height, a sigmoidal-type function with appropriate constraints is considered. Non-rigid substrate approximation is used in the evaluation of the transition thickness and the obtained numerical values are compared with the experimental ones. From these results, it can be claimed that the non-rigid substrate approach is appropriate to explain the relaxation process in the S–K growth mode.