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arXiv · 1610.00156

Ab initio model of amorphous zinc oxide (a-ZnO) and a-X_0.375 Z_0.625 O (X=Al, Ga and In)

Anup Pandey·Heath Scherich·D. A. Drabold
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Abstract

Density functional theory (DFT) calculations are carried out to study the structure and electronic structure of amorphous zinc oxide (a-ZnO). The models were prepared by the "melt-quench" method. The models are chemically ordered with some coordination defects. The effect of trivalent dopants in the structure and electronic properties of a-ZnO is investigated. Models of a-X_0.375 Z_0.625 O (X=Al, Ga and In) were also prepared by the "melt- quench" method. The trivalent dopants reduce the four-fold Zn and O, thereby introducing some coordination defects in the network. The dopants prefer to bond with O atom. The network topology is discussed in detail. Dopants reduce the gap in EDOS by producing defect states minimum while maintaining the extended nature of the conduction band edge.

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Anup Pandey, Heath Scherich, D. A. Drabold. 2016-10-01. Ab initio model of amorphous zinc oxide (a-ZnO) and a-X_0.375 Z_0.625 O (X=Al, Ga and In). https://doi.org/10.1016/j.jnoncrysol.2016.10.035

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