  We investigate island formation during heteroepitaxial growth using an
atomistic model that incorporates deposition, activated diffusion and stress
relaxation. For high misfit the system naturally evolves into a state
characterized by a narrow island size distribution. The simulations indicate
the existence of a strain assisted kinetic mechanism responsible for the
self-assembling process, involving enhanced detachment of atoms from the edge
of large islands and biased adatom diffusion.
