Layer-by-Layer Growth of AlN on ZnO(0001) Substrates at Room Temperature

We have grown AlN layers on atomically flat ZnO(0001) substrates by pulsed laser deposition at room temperature (RT) and investigated their structural properties. The reflection high-energy electron-diffraction (RHEED) intensity monitoring and atomic force microscopy (AFM) observations have revealed that the RT growth of AlN films proceeds by a layer-by-layer mode from the initial stage of the growth, and that the surfaces of the AlN films possess atomically-flat terraces separated by straight steps. We have also found that the AlN/ZnO heterointerfaces are atomically abrupt.