First-principles study of fluorine-doped zinc oxide

We present first-principles calculations for fluorine-doped zinc oxide (ZnO:F) by using density-functional theory. Under O-poor condition, fluorine substitution for oxygen (F(O)) is energetically favorable in ZnO. F(O) can effectively diminish oxygen vacancies. With high fluorine concentration, fluorine interstitial (F(i)) may appear. The high transition energies of F(O) and F(i) suggest that F(O) and F(i) could act as deep donor and acceptor which cannot provide free carriers in ZnO at room temperature. The increase of carriers and mobility in ZnO:F could not contribute from deep donor F(O), but may be due to the surface passivation effect of fluorine. (C) 2010 American Institute of Physics. [doi:10.1063/1.3492444]