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Title: Molecular dynamics simulation of annealed ZnO surfaces

Abstract

The effect of thermally annealing a slab of wurtzite ZnO, terminated by two surfaces, (0001) (which is oxygen-terminated) and (0001{sup ¯}) (which is Zn-terminated), is investigated via molecular dynamics simulation by using reactive force field (ReaxFF). We found that upon heating beyond a threshold temperature of ∼700 K, surface oxygen atoms begin to sublimate from the (0001) surface. The ratio of oxygen leaving the surface at a given temperature increases as the heating temperature increases. A range of phenomena occurring at the atomic level on the (0001) surface has also been explored, such as formation of oxygen dimers on the surface and evolution of partial charge distribution in the slab during the annealing process. It was found that the partial charge distribution as a function of the depth from the surface undergoes a qualitative change when the annealing temperature is above the threshold temperature.

Authors:
;  [1];  [2]
  1. School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia)
  2. Faculty of Engineering and Technology, Multimedia University, Melaka Campus, 75450 Melaka (Malaysia)
Publication Date:
OSTI Identifier:
22391534
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1657; Journal Issue: 1; Conference: PERFIK 2014: National Physics Conference 2014, Kuala Lumpur (Malaysia), 18-19 Nov 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANNEALING; ATOMS; CHARGE DISTRIBUTION; COMPUTERIZED SIMULATION; CUBIC LATTICES; DIMERS; HEATING; MOLECULAR DYNAMICS METHOD; OXYGEN; SLABS; SURFACES; TEMPERATURE DEPENDENCE; ZINC OXIDES

Citation Formats

Min, Tjun Kit, Yoon, Tiem Leong, and Lim, Thong Leng. Molecular dynamics simulation of annealed ZnO surfaces. United States: N. p., 2015. Web. doi:10.1063/1.4915201.
Min, Tjun Kit, Yoon, Tiem Leong, & Lim, Thong Leng. Molecular dynamics simulation of annealed ZnO surfaces. United States. doi:10.1063/1.4915201.
Min, Tjun Kit, Yoon, Tiem Leong, and Lim, Thong Leng. 2015. "Molecular dynamics simulation of annealed ZnO surfaces". United States. doi:10.1063/1.4915201.
@article{osti_22391534,
title = {Molecular dynamics simulation of annealed ZnO surfaces},
author = {Min, Tjun Kit and Yoon, Tiem Leong and Lim, Thong Leng},
abstractNote = {The effect of thermally annealing a slab of wurtzite ZnO, terminated by two surfaces, (0001) (which is oxygen-terminated) and (0001{sup ¯}) (which is Zn-terminated), is investigated via molecular dynamics simulation by using reactive force field (ReaxFF). We found that upon heating beyond a threshold temperature of ∼700 K, surface oxygen atoms begin to sublimate from the (0001) surface. The ratio of oxygen leaving the surface at a given temperature increases as the heating temperature increases. A range of phenomena occurring at the atomic level on the (0001) surface has also been explored, such as formation of oxygen dimers on the surface and evolution of partial charge distribution in the slab during the annealing process. It was found that the partial charge distribution as a function of the depth from the surface undergoes a qualitative change when the annealing temperature is above the threshold temperature.},
doi = {10.1063/1.4915201},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1657,
place = {United States},
year = 2015,
month = 4
}
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