InGaAs/GaAs Quantum Wells Grown by MBE on Artificial GaAs/Si(001) Substrates

InGaAs/GaAs quantum wells (QW) are grown by molecular beam epitaxy (MBE) on an artificial GaAs/Si substrate deviated by 6A degrees from the (001) plane in the [110] direction. Optimization of growth technology of artificial GaAs/Si substrates is performed. As optimization criteria, crystalline perfection of epitaxial films and their surface morphology were chosen. Artificial substrates with different crystallographic orientations of the GaAs buffer layer with respect to the direction of the Si surface deviation were grown. The methods of high-energy electron diffraction (RHEED) and X-ray diffraction were used to study the effect of the nucleation and growth regimes of GaAs/Si layers on their crystalline perfection. The surface morphology of the epitaxial layers was studied by RHEED (in situ) and atomic force microscopy (AFM) (ex situ). It is found that the transitional layers produced using the buffer layer 250 nm GaAs/2.70 nm GaP(001)/Si have optimum crystalline perfection and surface morphology. This layer was used to grow quantum wells and bulk layers. For these structures, the photoluminescence spectra at 5 and 77 K were obtained.