An investigation was made of the stability and electronic properties of defects formed by substitutional N in GaAs (NAs) plus interstitial H atoms, using first-principles total-energy calculations. The formation of strong NAs–H bonds was found when a single H atom was incorporated into the lowest-energy bond-centered position. This defect introduced an electrically active level into the GaAs band-gap. When two H atoms were incorporated, the stable NAs–H2* complex was found to be the lowest-energy configuration, with one H atom at the bond-centered position and the second H atom at an anti-bonding position. The electronic structure of this complex revealed a passivation of the gap level which restored the GaAs band-gap.

Stability and Electronic Structure of Hydrogen–Nitrogen Complexes in GaAs. W.Orellana, A.C.Ferraz: Applied Physics Letters, 2002, 81[20], 3816-8