Comment on: A new mechanism for reentrant behaviour in semiconductor epitaxy: a reflection high-energy electron diffraction study of the growth of GaAs(111)A thin films

Examination of experimental basis of a new mechanism for re-entrant bahaviour in reflection high energy electron diffraction intensity oscillations during homoepitaxial growth of GaAs on the (111)A surface has shown that surface morphology continue to change periodically under all the growth conditions. The observed re-entrant behaviour under specific diffraction conditions can be explained in terms of diffraction related mechanisms without invoking change of growth mode between 2D and 3D or 2D nucleation and step propogation as suggested in the original papers. This diffraction related mechanism is based on competition between coherent and incoherent diffraction processes as a result of a change on the average island size (length scale) in comparison to the coherence length of the electron beam.