Ab initio-based study for surface reconstructions and adsorption behavior on semipolar AlN() surfaces during metal–organic vapor-phase epitaxy growth

Abstract

The reconstructions and adsorption behavior of Al atoms on semipolar AlN() surfaces under various growth conditions are investigated by first-principles pseudopotential calculations. Our calculations reveal that there are several reconstructions depending on the growth conditions: the surface with Al adatoms is stabilized under H-poor conditions while that with Al–H and N–H bonds is favorable under H-rich conditions. We also find that the adsorption of Al atoms strongly depends on the surface reconstruction. The adsorption of Al atoms on the reconstructed surface under H-poor conditions is found to be much easier than that under H-rich conditions. These results indicate that similarly to the case of a polar AlN(0001) surface the growth of AlN on a semipolar () surface during metal–organic vapor-phase epitaxy is prominent under H-poor conditions.