Photoemission studies ofAlxGa1−xAs(100) surfaces grown by molecular-beam epitaxy

An As-stabilized ${\mathrm{Al}}_{0.7}$ ${\mathrm{Ga}}_{0.3}$As(100) surface grown by molecular-beam epitaxy was studied using photoemission techniques. Core-level shifts and relative emission intensities at the surface were used to deduce the surface structure. High-energy-electron-diffraction and surface-contamination-rate measurements were also made. The results indicate that this surface is very similar to the As-stabilized GaAs(100)-$c(2\mathrm{}\times 8)$ surface in structure with complete depletion of Al at the surface.