Influence of MBE Growth Conditions on Persistent Photoconductivily Effects in N-AlGaAs and Selectively Doped GaAs/AlGaAs Heterostructures

The influence of MBE growth conditions on persistent photoconductivity effects has been investigated both for N-Al 0.3 Ga 0.7 As layers and for selectively doped GaAs/N-Al 0.3 Ga 0.7 As heterostructures. The concentration of DX centers in the N-AlGaAs layer was proved to be independent of growth conditions, suggesting no relation to any native defect. For the selectively doped GaAs/N-AlGaAs heterostructure, in addition, persistent increase in 2DEG concentration after light exposure at 77 K was also proved to be independent of growth conditions.