Abstract

By using positron annihilation spectroscopy methods, we have experimentally demonstrated the creation of isolated zinc vacancy concentrations >1020 cm−3 in chemical vapor transport (CVT)-grown ZnO bulk single crystals. X-ray diffraction ω-rocking curve (XRC) shows the good quality of ZnO single crystal with (110) orientation. The depth analysis of Auger electron spectroscopy indicates the atomic concentrations of Zn and O are almost stoichiometric and constant throughout the measurement. Boltzmann statistics are applied to calculate the zinc vacancy formation energies (Ef) of ~1.3–1.52 eV in the sub-surface micron region. We have also applied Fick’s 2nd law to calculate the zinc diffusion coefficient to be ~1.07 × 10−14 cm2/s at 1100 °C. The zinc vacancies began annealing out at 300 °C and, by heating in the air, were completely annealed out at 700 °C.

Details

Title
Zn Vacancy Formation Energy and Diffusion Coefficient of CVT ZnO Crystals in the Sub-Surface Micron Region
Author
Parmar, Narendra S 1   VIAFID ORCID Logo  ; Boatner, Lynn A 2 ; Lynn, Kelvin G 3   VIAFID ORCID Logo  ; Ji-Won, Choi 4 

1  Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, Republic of Korea 
2  Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA 
3  Department of Physics and Astronomy, Washington State University, Pullman, WA, USA; Center for Materials Research, Washington State University, Pullman, WA, USA 
4  Center for Electronic Materials, Korea Institute of Science and Technology, Seoul, Republic of Korea; Department of Nanomaterials Science and Engineering, Korea University of Science and Technology, Daejeon, Republic of Korea 
Pages
1-8
Publication year
2018
Publication date
Sep 2018
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41598-018-31771-1
ProQuest document ID
2100850689
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.