Kinetic Monte Carlo Simulations of dislocations in heteroepitaxial growth

We determine the critical layer thickness for the appearance of misfit dislocations as a function of the misfit between the lattice constants of the substrate and the adsorbate from Kinetic Monte Carlo (KMC) simulations of heteroepitaxial growth. To this end, an algorithm is introduced which allows the off-lattice simulation of various phenomena observed in heteroepitaxial growth including critical layer thickness for the appearance of misfit dislocations, or self-assembled island formation. The only parameters of the model are deposition flux, temperature and a pairwise interaction potential between the particles of the system. Our results are compared with a theoretical treatment of the problem and show good agreement with a simple power law.