"Carbon acceptor
impurity in cubic BN, AlN, GaN, and in the GaAlN alloy
",
M. Marques, L.E.
Ramos , L.M.R. Scolfaro, L.K. Teles, and J.R.
Leite,
Proceedings of the 25th International Conference on the
Physics of Semiconductors ,
Osaka 2000,
edited by N. Miura and T. Ando, Springer-Verlag, Berlin (2001) p.
1411.
We present a systematic investigation of the electronic structure and stability of the C acceptor impurity in cubic (c) BN, AlN, and GaN by using the all electron Full Potential Linear Augmented Plane-Wave method and the local density and the large unit cell approximations. We found that C replacing N gives rise to a shallow acceptor level in the band-gap of these nitrides with an increasing activation energy as the cation atomic number decreases. The analysis of the impurity formation energies indicates that the CN center is favorable, as compared to MgGa. Since Ga-rich growth conditions are needed to achieve higher carrier concentrations in the molecular beam epitaxy grown c-phase materials, our results reinforce carbon as a good alternative acceptor dopant in c-nitrides.