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Title: Oxygen vacancy mediated enhanced photo-absorption from ZnO(0001) nanostructures fabricated by atom beam sputtering

Abstract

The nanoscale patterns created on the ZnO(0001) surfaces during atom beam irradiation have been investigated here for their photo absorption response. Preferential sputtering, during irradiation, promotes Zn-rich zones that serve as the nucleation centers for the spontaneous creation of nanostructures. Nanostructured surfaces with bigger (78 nm) nanodots, displaying hexagonal ordering and long ranged periodic behavior, show higher photo absorption and a ∼0.09 eV reduced bandgap. These nanostructures also demonstrate higher concentration of oxygen vacancies which are crucial for these results. The enhanced photo-response, as observed here, has been achieved in the absence of any dopant elements.

Authors:
; ; ;  [1]; ;  [2];  [3]
  1. Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005 (India)
  2. Inter University Accelerator Center, New Delhi 110067 (India)
  3. Department of Physics, Utkal University, Bhubaneswar 751004 (India)
Publication Date:
OSTI Identifier:
22597691
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 5; 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; ABSORPTION; ATOMS; BEAMS; DOPED MATERIALS; IRRADIATION; OXYGEN; PERIODICITY; QUANTUM DOTS; SPUTTERING; SURFACES; VACANCIES; ZINC OXIDES

Citation Formats

Solanki, Vanaraj, Joshi, Shalik R., Mishra, Indrani, Varma, Shikha, E-mail: shikha@iopb.res.in, Kabiraj, D., Avasthi, D. K., and Mishra, N. C. Oxygen vacancy mediated enhanced photo-absorption from ZnO(0001) nanostructures fabricated by atom beam sputtering. United States: N. p., 2016. Web. doi:10.1063/1.4960515.
Solanki, Vanaraj, Joshi, Shalik R., Mishra, Indrani, Varma, Shikha, E-mail: shikha@iopb.res.in, Kabiraj, D., Avasthi, D. K., & Mishra, N. C. Oxygen vacancy mediated enhanced photo-absorption from ZnO(0001) nanostructures fabricated by atom beam sputtering. United States. doi:10.1063/1.4960515.
Solanki, Vanaraj, Joshi, Shalik R., Mishra, Indrani, Varma, Shikha, E-mail: shikha@iopb.res.in, Kabiraj, D., Avasthi, D. K., and Mishra, N. C. Sun . "Oxygen vacancy mediated enhanced photo-absorption from ZnO(0001) nanostructures fabricated by atom beam sputtering". United States. doi:10.1063/1.4960515.
@article{osti_22597691,
title = {Oxygen vacancy mediated enhanced photo-absorption from ZnO(0001) nanostructures fabricated by atom beam sputtering},
author = {Solanki, Vanaraj and Joshi, Shalik R. and Mishra, Indrani and Varma, Shikha, E-mail: shikha@iopb.res.in and Kabiraj, D. and Avasthi, D. K. and Mishra, N. C.},
abstractNote = {The nanoscale patterns created on the ZnO(0001) surfaces during atom beam irradiation have been investigated here for their photo absorption response. Preferential sputtering, during irradiation, promotes Zn-rich zones that serve as the nucleation centers for the spontaneous creation of nanostructures. Nanostructured surfaces with bigger (78 nm) nanodots, displaying hexagonal ordering and long ranged periodic behavior, show higher photo absorption and a ∼0.09 eV reduced bandgap. These nanostructures also demonstrate higher concentration of oxygen vacancies which are crucial for these results. The enhanced photo-response, as observed here, has been achieved in the absence of any dopant elements.},
doi = {10.1063/1.4960515},
journal = {Journal of Applied Physics},
number = 5,
volume = 120,
place = {United States},
year = {Sun Aug 07 00:00:00 EDT 2016},
month = {Sun Aug 07 00:00:00 EDT 2016}
}
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