Electronic structure of Al- and Ga-doped ZnO films studied by hard X-ray photoelectron spectroscopy
Source abstract
Abstract
Al- and Ga-doped sputtered ZnO films (AZO, GZO) are semiconducting and metallic, respectively, despite the same electronic valence structure of the dopants. Using hard X-ray photoelectron spectroscopy we observe that both dopants induce a band in the electronic structure near the Fermi level, accompanied by a narrowing of the Zn 3d/O 2p gap in the valence band and, in the case of GZO, a substantial shift in the Zn 3d. Ga occupies substitutional sites, whereas Al dopants are in both substitutional and interstitial sites. The latter could induce O and Zn defects, which act as acceptors explaining the semiconducting character of AZO and the lack of variation in the optical gap. By contrast, mainly substitutional doping is consistent with the metallic-like behavior of GZO.
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Research context
OpenAlex topics: ZnO doping and properties · Copper-based nanomaterials and applications · Ga2O3 and related materials
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Universidad de Málaga 1 Lab. de Materiales & Superficies, Dpto. de Física Aplicada I, , 29071 Málaga, Spain
Laboratorio TASC 2 , IOM-CNR, S.S. 14 km 163.5, Basovizza, I-34149 Trieste, Italy
CEA 3 , DSM/IRAMIS/SPCSI, F-91191 Gif-sur-Yvette Cedex, France
Synchrotron SOLEIL 4 , BP 48, 91192 Gif-sur-Yvette, France and , UPMC Paris 06, CNRS UMR 7588, 4 Place Jussieu, 75005 Paris, France
Institut des NanoSciences de Paris 4 , BP 48, 91192 Gif-sur-Yvette, France and , UPMC Paris 06, CNRS UMR 7588, 4 Place Jussieu, 75005 Paris, France
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