Comparative study of the growth processes of GaAs, AlGaAs, InGaAs, and InAlAs lattice matched and nonlattice matched semiconductors using high-energy electron diffraction

We have examined the effect of growth temperature and growth interruption time on molecular-beam-epitaxial growth of GaAs, Al0.3Ga0.7As, and InxGa1−xAs on GaAs substrates and In0.53Ga0.47As and In0.52Al0.48As on InP substrates using dynamical reflection high-energy electron diffraction as an in situ probe. We have studied the time taken for a rough growth front to recover in the absence of growth as a function of growth temperature for these compounds. It is found that while GaAs and InGaAs surfaces can recover in 15–20 s under ideal growth conditions, Al0.3Ga0.7As surfaces take ≊45 s, and In0.52Al0.48As surfaces take several minutes to recover. Our results also suggest that smoothening of the growth front occurs by rearrangement of the surface atoms, rather than by re-evaporation. We have also studied the effect of strain induced by mismatch on growth modes in the case of InxGa1−xAs on GaAs. Our studies suggest that the presence of strain inhibits the surface migration of adatoms during growth and thus tends to generate a rougher growth front.