Published online by Cambridge University Press: 28 February 2011
Recent efforts employing reflection high energy electron diffiaction measurements to study the chemical beam epitaxial growth of GaAs is reviewed. A reaction model which assumes the dominance of Ga alkyls and their derivatives adsorbed on the growing surface can explain most of the growth results in a consistent way. Dynamic evolution of the reconstruction pattern of the adsorbed triethylgallium or trimethylgallium overlayer illustrates how the alkyl-Ga bonds are cleaved sequentially. The growth rate dependence on temperature and incident flux can be fitted quite well in this reaction model. In the absence of As flux, the existence of a metastable Ga alkyl overlayer makes possible the atomic layer epitaxy of GaAs.