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Title: Silver migration and trapping in ion implanted ZnO single crystals

Abstract

Potentially, group-Ib elements (Cu, Ag, and Au) incorporated on Zn sites can be used for p-type doping of ZnO, and in the present paper, we use ion implantation to introduce Ag atoms in wurtzite ZnO single crystals. Monitoring the Li behavior, being a residual impurity in the crystals, as a tracer, we demonstrate that Zn interstitials assist the Ag diffusion and lead to Ag pile-up behind the implanted region after annealing above 800 °C. At even higher temperatures, a pronounced Ag loss from the sample surface occurs and concurrently the Ag atoms exhibit a trap-limited diffusion into the crystal bulk with an activation energy of ∼2.6 eV. The dominant traps are most likely Zn vacancies and substitutional Li atoms, yielding substitutional Ag atoms. In addition, formation of an anomalous multipeak Ag distribution in the implanted near-surface region after annealing can be attributed to local implantation-induced stoichiometry disturbances leading to trapping of the Ag atoms by O and Zn vacancies in the vicinity of the surface and in the end-of-range region, respectively.

Authors:
; ; ; ;  [1]
  1. Department of Physics, Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1048 Blindern, N-0316 Oslo (Norway)
Publication Date:
OSTI Identifier:
22596978
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 18; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACTIVATION ENERGY; ANNEALING; ATOMS; COPPER; DIFFUSION; GOLD; IMPURITIES; INTERSTITIALS; ION IMPLANTATION; LITHIUM; MIGRATION; MONOCRYSTALS; SILVER; STOICHIOMETRY; SURFACES; TEMPERATURE RANGE 0400-1000 K; TRAPPING; VACANCIES; ZINC OXIDES

Citation Formats

Azarov, Alexander, Vines, Lasse, Rauwel, Protima, Monakhov, Edouard, and Svensson, Bengt G. Silver migration and trapping in ion implanted ZnO single crystals. United States: N. p., 2016. Web. doi:10.1063/1.4949331.
Azarov, Alexander, Vines, Lasse, Rauwel, Protima, Monakhov, Edouard, & Svensson, Bengt G. Silver migration and trapping in ion implanted ZnO single crystals. United States. doi:10.1063/1.4949331.
Azarov, Alexander, Vines, Lasse, Rauwel, Protima, Monakhov, Edouard, and Svensson, Bengt G. Sat . "Silver migration and trapping in ion implanted ZnO single crystals". United States. doi:10.1063/1.4949331.
@article{osti_22596978,
title = {Silver migration and trapping in ion implanted ZnO single crystals},
author = {Azarov, Alexander and Vines, Lasse and Rauwel, Protima and Monakhov, Edouard and Svensson, Bengt G.},
abstractNote = {Potentially, group-Ib elements (Cu, Ag, and Au) incorporated on Zn sites can be used for p-type doping of ZnO, and in the present paper, we use ion implantation to introduce Ag atoms in wurtzite ZnO single crystals. Monitoring the Li behavior, being a residual impurity in the crystals, as a tracer, we demonstrate that Zn interstitials assist the Ag diffusion and lead to Ag pile-up behind the implanted region after annealing above 800 °C. At even higher temperatures, a pronounced Ag loss from the sample surface occurs and concurrently the Ag atoms exhibit a trap-limited diffusion into the crystal bulk with an activation energy of ∼2.6 eV. The dominant traps are most likely Zn vacancies and substitutional Li atoms, yielding substitutional Ag atoms. In addition, formation of an anomalous multipeak Ag distribution in the implanted near-surface region after annealing can be attributed to local implantation-induced stoichiometry disturbances leading to trapping of the Ag atoms by O and Zn vacancies in the vicinity of the surface and in the end-of-range region, respectively.},
doi = {10.1063/1.4949331},
journal = {Journal of Applied Physics},
number = 18,
volume = 119,
place = {United States},
year = {Sat May 14 00:00:00 EDT 2016},
month = {Sat May 14 00:00:00 EDT 2016}
}
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