Influence of MBE growth conditions on deep electronic states at the inverted GaAs/AlAs interface

Abstract

Under standard MBE growth conditions, a series of electron traps is concentrated near the inverted. GaAs/AlAs interface (GaAs grown on top of AlAs). These levels have been identified as being due to native point defects on the AlAs side of the heterointerface. The particular influence of As/sub 4/ flux, growth temperature, and growth rate is examined with respect to the intrinsic levels at the inverted GaAs/AlAs interface. It is shown that the structural and compositional perfection of the inverted interface is strongly affected by excess arsenic during growth. Moreover, it is found that the accumulation of the dominant, arsenic vacancy-related defect on the AlAs side of the inverted interface is neither influenced by the As/sub 4/ flux, nor by the growth rate.