Electron-Energy-Loss Scattering near a Single Misfit Dislocation at the GaAs/GaInAs Interface

Abstract

Spatially resolved electron-energy-loss scattering has been used to study changes in the inelastic scattering near the bulk band-gap energy for locations near the GaAs-${\mathrm{Ga}}_{0.85}$ ${\mathrm{In}}_{0.15}$As interface. We observe the expected bulk band gap on either side of the interface. At a single interface-misfit dislocation we observe scattering which is consistent with an excitation of transitions between a localized state near the dislocation and the crystal conduction band. Within this interpretation, the energy of the state is estimated to be 0.7 ± 0.05 eV above the GaAs valence-band maximum.