Observation of (5×1) surface reconstruction and surface smoothing of molecular‐beam epitaxial ZnS:Ga by post‐annealing

The (2×1) and (5×1) surface reconstructions accompanied with the surface smoothing have been observed at ZnS:Ga layers grown on (100) GaAs by molecular‐beam epitaxy (MBE) and followed by postannealing at 600 °C for 20 min. The origin of these reconstructions are discussed and it is suggested that the reconstruction of (5×1) is due to the misfit strain relaxation in the ZnS:Ga epilayer or at the ZnS:Ga/GaAs interface. The simple lattice model of (2×1) and (5×1) surfaces are proposed on the basis of a dimer model. It is confirmed that the surface lattice models proposed give the diffraction patterns of (2×1) and (5×1) by a laser simulation.