Mechanisms for p-type behavior of ZnO, Zn${}_{1-x}$Mg${}_x$O and related oxide semiconductors

Abstract

Possibilities of turning intrinsically n-type oxide semiconductors like ZnO and Zn${}_{1-x}$Mg${}_x$O into p-type materials are investigated. Motivated by recent experiments on Zn${}_{1-x}$Mg${}_x$O doped with nitrogen we analyze the electronic defect levels of point defects N${}_{\mathrm{O}}$, v${}_{\mathrm{Zn}}$, and N${}_{\mathrm{O}}$-v${}_{\mathrm{Zn}}$ pairs in ZnO and Zn${}_{1-x}$Mg${}_x$O by means of self-interaction-corrected density functional theory calculations. We show how the interplay of defects can lead to shallow acceptor defect levels, although the levels of individual point defects N${}_{\mathrm{O}}$ are too deep in the band gap for being responsible for p-type conduction. We relate our results to p-type conduction paths at grain boundaries seen in polycrystalline ZnO and develop an understanding of a p-type mechanism which is common to ZnO, Zn${}_{1-x}$Mg${}_x$O, and related materials.

7 pages, 7 figures

References in corpus (2)

• Band Structure and Effective Masses of ZnMgO
• Comparison of density functionals for nitrogen impurities in ZnO

Cited by in corpus (1)

• Interplay of charge-transfer and Mott-Hubbard physics approached by an efficient combination of self-interaction correction and dynamical mean-field theory