Ab initio calculations predict that Be is a shallow acceptor in GaN. Its thermal ionization energy is 0.06 eV in wurtzite GaN; the level is valence resonant in the zincblende phase. Be incorporation is severely limited by the formation of . It is shown, however, that co-incorporation with reactive species can enhance the solubility. H-assisted incorporation should lead to high doping levels in metal-organic-chemical-vapor deposition growth after post-growth annealing at about 850 K. Be-O co-incorporation produces high Be and O concentrations at molecular beam epitaxy growth temperatures.
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© 1997 American Institute of Physics.
1997
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