Observation of ALE Growth Process of ZnTe by RHEED

The ALE growth process of ZnTe is investigated with RHEED intensity observation. It is found that when the substrate temperature is sufficiently low, physisorbed Zn and Te adatoms are present on the Zn and Te-coverd surfaces, respectively. The ZnTe layers not less than monolayer grow during one cycle of ALE by the presence of these excess adatoms. Evaporation of the surface atoms occurs during growth suspension. First, the excess adatoms desorb, and then Zn and Te atomic layers sublime with different sublimation time constants. At high temperatures, the layer-by-layer evaporation occurs, as is verified by RHEED intensity oscillation during the sublimation process.