Unintentionally doped hydrogen removal mechanism in Li doped ZnO

Up to now, the influence of unintentionally doped H in ZnO on electronic properties still perplexes us. Recently, it had been found in experiment that the introduction of Li would dramatically decrease the stability of H. In order to clarify the inner physical mechanism behind the phenomenon, we investigated the formation energy and the potential barrier height for H movement in ZnO with different configuration of doped Li by employing first-principle calculation. It is revealed that interstitial Li (Lii) facilitates the escape of H from trap of ZnO lattice and reduces the potential barrier due to electrostatic interaction. Our methodology can also be extended to analyze the stability of trace element in other semiconductors.