paper

Ab initio shallow acceptor levels in gallium nitride

arXiv:cond-mat/9610045

Abstract

Impurity levels and formation energies of acceptors in wurtzite GaN are predicted ab initio. Be_Ga is found to be the shallow (thermal ionization energy $\sim$ 0.06 eV); $M g_{G a}$ and $Z n_{G a}$ are mid-deep acceptors (0.23 eV and 0.33 eV respectively); $C a_{G a}$ and $C d_{G a}$ are deep acceptors ( $\sim$ 0.65 eV); $S i_{N}$ is a midgap trap with high formation energy; finally, contrary to recent claims, $C_{N}$ is a deep acceptor (0.65 eV). Interstitials and heteroantisites are energetically not competitive with substitutional incorporation.

4 pages, to appear in "The Physics of Semiconductors"