SIMULTANEOUS MONITORING OF DIFFERENT SURFACE PROCESSES ON DIFFERENT STREAKS OF THE REFLECTION HIGH-ENERGY ELECTRON-DIFFRACTION PATTERN

The recently discovered additional phase shift of reflection high energy electron diffraction (RHEED) intensity oscillations at heterointerfaces significantly deepens the analysis of surface dynamics using RHEED. The evolution of the phase shift is different for the (01) and (00) streaks of the same RHEED pattern because the two streaks show a different sensitivity on surface morphology: whereas diffraction into (01) streaks requires good lateral periodicity of the surface, no lateral periodicity is required for diffraction into the (00) streak. Therefore, the signal on the (00) streak should be most sensitive towards steps running along the electron beam, while the (01) beams sample mostly terraces. We demonstrate the potential and sensitivity of this effect using GaAs-AlAs(100) interfaces and discuss its compatibility with current models of RHEED oscillations. The effects is then applied to characterize the incorporation dynamics of segregating and non-segregating dopants.