ORIGIN OF ELECTRON-DIFFRACTION OSCILLATIONS DURING CRYSTAL-GROWTH

Measurements of the intensity oscillation phase of reflection high-ene rgy electron diffraction during molecular beam epitaxy growth of GaAs and AlAs indicate that the oscillations are due to an interference eff ect within the surface reconstruction layer forming on the growing lay er. The experimental results along a low-symmetry azimuth are explaine d by a basic theoretical model using only the layer thickness as a fit ting parameter. Our conclusions are supported by energy loss measureme nts showing the absence of diffuse inelastic contributions with a diff erent phase.