Nucleation in Si(001) homoepitaxial growth

From low energy electron microscopy observations of the surface topography of Si(001) during homoepitaxial growth at 650°C, we have determined the nucleation density profile on top of a “base” island, and the distribution of the base island radius at the time of nucleation.Comparison with homogeneous nucleation theory yields a typical critical nucleus size of ˜ 650 dimers, and allows nucleation on Si(001) to be understood in a common framework with equilibrium step-edge fluctuations and 2D island ripening. © 1996 The American Physical Society.