Theoretical investigation of the growth of GaAs on Si(001), Si(110), Si(111), Si(113) and Si(331)

The atomic structure of the first atomic layers of GaAs over Si(hhl) substrates were studied by ab initio calculations employing the density functional theory (DFT). Layered converged Si(hhl) supercells were used to investigate the interfacial interaction with the first Ga/GaAs and As/GaAs layers. Formation energies and volumetric charge densities differences confirms the stronger tendency of the As atoms, compared to Ga atoms, to form bonds with the different Si(hhl) surfaces. We confirm the reported experimental order sequence Si(111) > Si(001) > Si(110) in internal crystal structure quality of GaAs growth via the calculation of the interfacial energy, work of adhesion and total charge transfer. From this work, we expand the sequence in internal crystal structure quality as Si(111) > Si(331) ≥ Si(001) > Si(113) ≥ Si(110).