A video-based analysis system for reflection high-energy electron diffraction (RHEED) is described which simultaneously measures the intensities and profiles of multiple diffraction beams. This system is used to record real-time RHEED intensity oscillations for layer-by-layer epitaxial growth. Fast Fourier transform analysis of the oscillation data is used to directly determine the growth rate and to accurately obtain phase information about the oscillations. This system is demonstrated and compared to other methods of recording RHEED oscillation data.

The intensities of several reflection high-energy electron diffraction (RHEED) beams have been recorded during molecular-beam epitaxial growth of GaAs(100) using a novel video intensity measurement system that records multiple RHEED beam intensities simultaneously. The RHEED beam intensities were recorded at varying angles of incidence and crystal substrate azimuth angles. Strong oscillations in the intensities in specular and nonspecular beams with the same period but varying phases have been measured. As noted by other investigators, the phase relationship of the oscillations of the various beams has been found to vary with incident and azimuthal angle. The results are examined with regard to recent studies of the role of Kikuchi processes on the phase of the specular beam. In contrast to other reports, it is found that although the diffracted intensities in the vicinity of the elastically diffracted beams are influenced by inelastically scattered electrons from the Kikuchi lines, these effects can not account for all the phase behavior observed.