Second derivative ballistic electron emission spectrocopy in Au/(AlGa)As

Abstract

Our current study focuses on an analysis of the ballistic electron emission microscopy(BEEM) spectra of Au/(AlGa) As heterostructures to estimate quantitatively the effect of thecarrier scattering in the metal, at the metal-semiconductor (ms) interface and in thesemiconductor on the multivalley carrier transport. The second derivative (SD)-BEEM spectra,representing the heterostructure transmission coefficient, show explicit partitioning of thecontribution of different transport channels (T, L and X conduction valleys). Our analysis of SD-BEEM spectra by the developed theoretical model indicates that about 85-92% of the BEEMelectrons are scattered at the nonepitaxial Au/GaAs interface. We also show that initial electrondistribution among the conduction bands of the semiconductor, specified by the ms interfacescattering, is modified by the further hot-electron transport inside the semiconductor.