Band discontinuities at the (100) interfaces with In- and P-insertion layers: Effects of isoelectronic impurity layers

Abstract We have theoretically investigated the valence-band discontinuities ( ΔE v ) at the (100) GaAs AlAs interfaces with the In- and P-insertion layers by using a self-consistent sp 3 s ∗ tight-binding method. At the interfaces with one In monolayer (GaAs In AsAl) and two In monolayers (GaAs In As In AsAl), the calculations give ΔE v = 0.50eV, which is practically equal to ΔE v = 0.51 eV at the interface with no insertion layers. This result is consistent with our x-ray photoelectron spectroscopy measurements for the samples grown by the molecular beam epitaxy. At the interface with one P monolayer (AsGa P AlAs), the calculation gives ΔE v = 0.47 eV, which is smaller by 0.04 eV than ΔE v , with no insertion layers. The asymmetric configuration (Ga P Al) changes ΔE v slightly, while the symmetric configurations (As In As and As In As In As) do not change it.