A model was proposed which gave a fundamental limiting factor for the growth of epilayers on the (111)B face. The model was that the As-trimer structure of As-stabilized (111)B surface with the (2 x 2) reconstruction disturbs the incorporation of group III atoms into lattice sites. This model gives the explanation to most of the reported properties in the growth of GaAs and AlGaAs on (111)B substrates. This model was verified by comparing the growth rate of GaAs layers grown by molecular-beam epitaxy over mesa-shaped substrates with (111)A and (111)B sidewalls using As4 and As2. Moreover, the cause of micro-twins found in transmission electron microscopy images of AlGaAs grown on (111)B GaAs at a low Ts could be at least partly explained by this model. Surface Reconstruction Limited Mechanism of Molecular-Beam Epitaxial Growth of AlGaAs on (111)B Face. T.Hayakawa, M.Morishima, S.Chen: Applied Physics Letters, 1991, 59[25], 3321