Monte Carlo growth and in situ characterisation for AlxGa1−xAs heteroepitaxy

We present a kinetic Monte Carlo model describing the growth of AlxGa1−xAs heterostructure and including a local photoemission model with reflection high-energy electron diffraction (RHEED) intensity for comparison. The model assumes growth under As rich conditions typical for molecular beam epitaxy (MBE). We have examined the AlxGa1−xAs morphology with 0 ⩽ x ⩽ 1 and the growth of normal and inverted interface of AlAs–GaAs system. We show, as has been observed experimentally [J. Electrochem. Soc. 129 (1982) 824; J. Vac. Sci. Technol. B 4 (2) (1986) 590], a roughness AlxGa1−xAs front profile for high Al concentrations and a difference in the quality of the two AlAs–GaAs interfaces due to a lower diffusivity of Al atoms compared to Ga atoms.