Self-consistent solutions of electronic wave functions at GaAs–AlxGa1–xAs interfaces

Abstract

We report the first study of the self-consistent electronic wave functions at a heavily doped GaAs–AlxGa1–xAs interface. The doping densities in the GaAs are between 10^17 and 10^19 cm^–3. These doping densities are characteristic of tunnel structure devices. The Schrödinger equation is solved self-consistently in the Hartree approximation. Some of the more important results of our calculations include the fact that there is only a single subband level in the well for a wide range of biases. This level is also fairly loosely bound (bound by a few meV) in spite of the fact that the notch at the interface is on the order of a 100 meV. In accumulation layers, the potential at the interface is somewhat similar to the non-self-consistent one. However, in depletion layers the self-consistent potential can be substantially different from the one obtained in the Thomas–Fermi approximation.