  We perform a comprehensive study of the formation of three dimensional
(pyramidal) structures in a large range of conditions, including the possible
evaporation of adatoms from the surface and the presence of surface defects. We
compare our computer simulations to theoretical calculations of the growth and
find good agreement between them. This work clarifies precedent studies of
three dimensional growth and predicts the island size distributions obtained in
the different regimes. Finally, we show how our analysis can be used to
interpret experimental data.
