Effects of DX center and spatial distribution of electrons on the density of two-dimensional electron gas in modulation-doped AlGaAs/GaAs heterojunction structure

The equilibrium density of two-dimensional electron gas in a modulation-doped AlGaAs/GaAs heterojunction structure has been studied by considering the deep electron traps (i.e., DX center) in doped AlGaAs layer, the spatial distribution of electrons in three conduction-band minima (Γ, L, and X), and the heavy doping effect. It is shown that the amount of conduction band-bending increases and the equilibrium density of two-dimensional electron gas decreases significantly as a result of incorporating these effects.