Imaging of layer by layer growth processes during molecular beam epitaxy of GaAs on (111)A substrates by scanning electron microscopy

When we use a scanning electron microscope-molecular beam epitaxy system with a GaAs (111)A substrate that dramatically improves the flatness of the growing surface, it makes possible detailed observations of the near-equilibrium growth processes of island nucleation, coalescence, and step motion. These observations allow the quantitative analysis of the growth processes based on the standard model of crystal growth. As an example, the Ga adatom surface diffusion length is directly determined from the dependence of measured step velocity on the Ga arrival rate. © 1998 American Institute of Physics.