BALLISTIC-ELECTRON-EMISSION MICROSCOPY OF INAS GA1-XALXAS RELAXED HETEROSTRUCTURE INTERFACES/

The barrier height of Au/InAs/AlGaAs as a function of AlAs content (x = 0-1.0) was measured using ballistic electron emission microscopy (BE EM). The InAs interlayer was introduced here to change the contact beh aviour between Au and AlGaAs. The measured dependence of barrier heigh t with Al content (x) was found to differ from that in the direct Au/A lGaAs contact. Also, the variation of barrier height over space was su ccessfully recorded, which suggests the influence of local potentials (defects) upon local barriers. The STM image of the InAs surface revea led highly relaxed surface structures, which may explain the observed inhomogeneity of the InAs/AlGaAs interface.