N-S共掺ZnO的第一性原理研究

First-principles study of N-S co-doped ZnO

通过第一性原理方法计算了未掺杂、N单掺和N-S共掺ZnO的电子结构。对态密度的计算发现,N单掺时会在价带顶费米能级附近形成一个局域性很强的能级,N-S共掺后N的局域性减弱,费米能级更加深入价带导致空穴浓度增加;对有效质量的计算发现,共掺时的有效质量较单掺时减小。计算结果表明,N-S共掺相对于N单掺有利于形成p型ZnO。

We have performed first-principle calculations on the electronic structure and effective mass of pure ZnO, and N single-doped and N-S co-doped ZnO. According to the DOS results, in the N single-doped case the impurity states are rather localized. In the N-S co-doped case, however, the PDOS of N is delocalized and the Fer- mi level penetrates more deeply into the valence band, which means that the hole concentration will increase. In addition, in the N-S co-doped case, the effective masses are smaller than that in the N single-doped case. The a- bove results suggest that N-S co-doping is a better way to prepare p-type ZnO than doping with N alone.