  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.
