REFLECTION HIGH-ENERGY ELECTRON-DIFFRACTION STUDIES OF THE GROWTH OF INAS/GA1-XINXSB STRAINED-LAYER SUPERLATTICES

We have used reflection high-energy electron diffraction to study the surface periodicity of the growth front of InAs/GaInSb strained-layer superlattices (SLSs). We found that the apparent surface lattice spacing reproducibly changed during layers which subsequent x-ray measurements indicated were coherently strained. Abrupt changes in the measured streak spacings were found to be correlated to changes in the growth flux. The profile of the dynamic streak spacing was found to be reproducible when comparing consecutive periods of a SLSs or different SLSs employing the same shuttering scheme at the InAs/GaInSb interface. Finally, when the interface shuttering scheme was changed, it was found that the dynamic streak separation profile also changed. Large changes in the shuttering scheme led to dramatic differences in the streak separation profile, and small changes in the shuttering scheme led to minor changes in the profile. In both cases, the differences in the surface periodicity profile occured during the parts of the growth where the incident fluxes differed.