TY - JOUR
T1 - Chemical reactions of ammonia with polar and non-polar nitride semiconductor surfaces
AU - Fritsch, J.
AU - Sankey, O. F.
AU - Schmidt, Kevin
AU - Page, J. B.
N1 - Funding Information:
This work was supported by the Alexander-von Humboldt foundation through a Feodor-Lynen-Forschungsstipendium, the National Science Foundation (Grant No. DMR-9632635 and Grant No. DMR-9510182), and the Office of Naval Research (N00014-95-1-0122).
PY - 1999/6/1
Y1 - 1999/6/1
N2 - We present results from ab-initio local-orbital calculations performed to study the impact of ammonia on GaN. We focus on chemical reactions on the non-polar (101̄0) and (112̄0) surfaces as well as the dissociative adsorption of NH3 on GaN(0001̄), for which an energy barrier is obtained by computing the potential energy surface. For the adsorption of NH3 on GaN(0001̄), finite-temperature molecular-dynamics simulations show that the molecule splits into NH2 and H. The NH2 group binds to two of the three second-layer Ga atoms neighboring the vacancy, while the dissociating H binds to a first-layer nitrogen atom. This reaction lowers the total energy of the system by 2.05 eV. The energy barrier estimated for dissociative adsorption of NH2 and H on the vacancy p(2×2) reconstruction of the GaN(0001̄) surface is 0.5 eV.
AB - We present results from ab-initio local-orbital calculations performed to study the impact of ammonia on GaN. We focus on chemical reactions on the non-polar (101̄0) and (112̄0) surfaces as well as the dissociative adsorption of NH3 on GaN(0001̄), for which an energy barrier is obtained by computing the potential energy surface. For the adsorption of NH3 on GaN(0001̄), finite-temperature molecular-dynamics simulations show that the molecule splits into NH2 and H. The NH2 group binds to two of the three second-layer Ga atoms neighboring the vacancy, while the dissociating H binds to a first-layer nitrogen atom. This reaction lowers the total energy of the system by 2.05 eV. The energy barrier estimated for dissociative adsorption of NH2 and H on the vacancy p(2×2) reconstruction of the GaN(0001̄) surface is 0.5 eV.
UR - http://www.scopus.com/inward/record.url?scp=0033149285&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033149285&partnerID=8YFLogxK
U2 - 10.1016/S0039-6028(99)00293-9
DO - 10.1016/S0039-6028(99)00293-9
M3 - Conference article
AN - SCOPUS:0033149285
SN - 0039-6028
VL - 427-428
SP - 298
EP - 303
JO - Surface Science
JF - Surface Science
T2 - Proceedings of the 1998 9th International Conference on Vibrations at Surfaces (VAS9)
Y2 - 12 October 1998 through 16 October 1998
ER -