Ab initio-based study for surface reconstructions and adsorption behavior on semipolar AlN(11(2)over-bar2) surfaces during metal-organic vapor-phase epitaxy growth

摘要

The reconstructions and adsorption behavior of Al atoms on semipolar AlN(11 (2) over bar2) 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 (11 (2) over bar2) surface during metal-organic vapor-phase epitaxy is prominent under H-poor conditions. (C) 2015 The Japan Society of Applied Physics