Kinetic model of GaAs(100) growth from molecular beams

A kinetic model for the growth of GaAs(100) by molecular beam epitaxy is constructed. The elementary processes at the surface are analyzed, including chemisorption of atoms and molecules, incorporation of atoms into the crystal, decomposition of the crystal, and desorption of group-III atoms and group-v molecules in vacuum. The sticking coefficients and rate constants are obtained from a direct comparison with experimental darn. The model can be used to determine the desorbed and reflected fluxes, the growth rate, and the coverage by groups III and V atoms as functions of the incident fluxes and temperature. The model can also be used to estimate the limits of validity of the thermodynamic approach and the minimum epitaxy temperature. The results of the calculations show good agreement with the experimental observations. (C) 1997 American Institute of Physics. [S1063-7850(97)01201-9].