Hot-electron transmission through metal-metal interfaces: a study of Au/Fe/Au trilayers on GaAs substrates

Hot-electron scattering at metal-metal interfaces has been studied in the case of Au/Fe/Au trilayers where the thickness of Fe is varied between 0 and 10Å, using Ballistic Electron Emission Microscopy (BEEM). It has been found that the presence of the Fe layer sandwiched between the Au layers causes a considerable reduction of electrons transmitted through the structure. It is likely that the losses are primarily due to the strong scattering at the metal-metal interfaces and the BEEM technique is highly sensitive to such scattering. A Monte Carlo simulation has been carried out in the case of ideal interface structures and the results indicate that the interface scattering is a dominant factor.