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Title: Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals

Abstract

This work reports on the effects of a deep high-dose hydrogen ion implant on damage accumulation, defect retention, and silver diffusion in silver implanted ZnO crystals. Single-crystal ZnO samples were implanted with Ag ions in a region ∼150 nm within the surface, and some of these samples were additionally implanted with hydrogen ions to a dose of 2 × 10{sup 16 }cm{sup −2}, close to the depth ∼250 nm. Rutherford backscattering/ion channeling measurements show that crystal damage caused by Ag ion implantation and the amount of defects retained in the near surface region following post-implantation annealing were found to diminish in the case with the H implantation. On the other hand, the additional H ion implantation resulted in a reduction of substitutional Ag atoms upon post-implantation annealing. Furthermore, the presence of H also modified the diffusion properties of Ag atoms in ZnO. We discuss these findings in the context of the effects of nano-cavities on formation and annihilation of point defects as well as on impurity diffusion and trapping in ZnO crystals.

Authors:
 [1];  [2]
  1. Department of Physics, State University of New York at Albany, Albany, New York 12222 (United States)
  2. College of Nanoscale Science and Engineering, State University of New York Polytechnic Institute, Albany, New York 12203 (United States)
Publication Date:
OSTI Identifier:
22597784
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANNEALING; ANNIHILATION; ATOMS; BUILDUP; CRYSTAL DEFECTS; DEFECTS; DIFFUSION; DOPED MATERIALS; DOSES; HYDROGEN IONS; ION CHANNELING; ION IMPLANTATION; MONOCRYSTALS; POINT DEFECTS; RUTHERFORD BACKSCATTERING SPECTROSCOPY; SILVER; SILVER IONS; SURFACES; ZINC OXIDES

Citation Formats

Yaqoob, Faisal, and Huang, Mengbing, E-mail: mhuang@sunypoly.edu. Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals. United States: N. p., 2016. Web. doi:10.1063/1.4958849.
Yaqoob, Faisal, & Huang, Mengbing, E-mail: mhuang@sunypoly.edu. Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals. United States. doi:10.1063/1.4958849.
Yaqoob, Faisal, and Huang, Mengbing, E-mail: mhuang@sunypoly.edu. Thu . "Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals". United States. doi:10.1063/1.4958849.
@article{osti_22597784,
title = {Effects of high-dose hydrogen implantation on defect formation and dopant diffusion in silver implanted ZnO crystals},
author = {Yaqoob, Faisal and Huang, Mengbing, E-mail: mhuang@sunypoly.edu},
abstractNote = {This work reports on the effects of a deep high-dose hydrogen ion implant on damage accumulation, defect retention, and silver diffusion in silver implanted ZnO crystals. Single-crystal ZnO samples were implanted with Ag ions in a region ∼150 nm within the surface, and some of these samples were additionally implanted with hydrogen ions to a dose of 2 × 10{sup 16 }cm{sup −2}, close to the depth ∼250 nm. Rutherford backscattering/ion channeling measurements show that crystal damage caused by Ag ion implantation and the amount of defects retained in the near surface region following post-implantation annealing were found to diminish in the case with the H implantation. On the other hand, the additional H ion implantation resulted in a reduction of substitutional Ag atoms upon post-implantation annealing. Furthermore, the presence of H also modified the diffusion properties of Ag atoms in ZnO. We discuss these findings in the context of the effects of nano-cavities on formation and annihilation of point defects as well as on impurity diffusion and trapping in ZnO crystals.},
doi = {10.1063/1.4958849},
journal = {Journal of Applied Physics},
number = 4,
volume = 120,
place = {United States},
year = {Thu Jul 28 00:00:00 EDT 2016},
month = {Thu Jul 28 00:00:00 EDT 2016}
}
  • The effects of annealing on the optical properties and defect/dopant evolution in wurtzite (0001) ZnO single crystals implanted with Er ions are studied using a combination of Rutherford backscattering/channeling spectrometry and photoluminescence measurements. The results suggest a lattice recovery behavior dependent on ion dose and involving formation/evolution of an anomalous multipeak defect distribution, thermal stability of optically active Er complexes, and Er outdiffusion. An intermediate defect band occurring between the surface and ion-induced defects in the bulk is stable up to 900 °C and has a photoluminescence signature around 420 nm well corresponding to Zn interstitials. The optical activity of the Ermore » atoms reaches a maximum after annealing at 700 °C but is not directly associated to the ideal Zn site configuration, since the Er substitutional fraction is maximal already in the as-implanted state. In its turn, annealing at temperatures above 700 °C leads to dissociation of the optically active Er complexes with subsequent outdiffusion of Er accompanied by the efficient lattice recovery.« less
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