Journal of Physical Studies 23(2), Article 2702 [6 pages] (2019)
DOI: https://doi.org/10.30970/jps.23.2702

DFT STUDY OF NATIVE POINT DEFECTS IN (ZnO)n (n = 34, 60) NANOCLUSTERS

R. V. Bovhyra1, O. V. Bovgyra2, D. I. Popovych1, A. S. Serednytsky1

1Pidstryhach Institute for Applied Problems of Mechanics and Mathematics NAS Ukraine,
3-b, Naukova St., Lviv, UA-79060, Ukraine
2Faculty of Physics, Ivan Franko National University of Lviv,
8a, Kyrylo and Mefodiy St, Lviv, UA-79005, Ukraine

Density-functional theory studies within the GGA+U approach of the structural and electronic properties of (ZnO)$_n$ ($n$=34, 60) nanoclusters with native point defects (zinc vacancy (V$_\emph{\emph{Zn}}$), oxygen vacancy (V$_\emph{\emph{O}}$), zinc antisite (Zn$_\emph{\emph{O}}$), and, finally, oxygen antisite (O$_\emph{\emph{Zn}}$)) were performed. The optimization of the structure geometry, as well as the band structure research, was performed. The values for the formation energy, HOMO-LUMO gap, and the partial density of states for each cluster were investigated to establish the influence of the defects on the electronic properties of the (ZnO)$_n$nanoclusters.

It was determined that the most favorable defects of the clustersХ structure were Zn and O vacancies. A zinc vacancy introduces partially occupied states into the bandgap close to the HOMO state of the cluster. These states explain the acceptor behavior of V$_\emph{\emph{Zn}}$ in ZnO. It has two deep acceptor levels above HOMO with values 1.2 and 2 eV. This particular defect has the lowest formation energy value among all acceptor-type defects. An oxygen vacancy is a deep donor type of defect with the lowest formation energy values among all donor type defects. In our case of neutral-type defects, V$_\emph{\emph{O}}$ induces one deep and localized one-electron state into the bandgap. A zinc antisite defect generates both deep and shallow donor levels. It has a very high formation energy and can be treated as a complex of both the oxygen vacancy and zinc interstitial defects. The oxygen antisite is an acceptor-type defect with very high formation energy.

PACS number(s): 73.22.-f, 73.20.At, 61.72.Ww

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References
  1. C. Jagadish, S. Pearton, \emph{Zinc Oxide Bulk, Thin Films and Nanostructures: Processing Properties and Applications} (Elsevier, 2006).
  2. Ü. Özgür et al., Appl. Phys. 98, 041301 (2005);
    CrossRef
  3. Ya. V. Bobitski et al., J. Nano-Electron. Phys. 9(5), 05008 (2017);
    CrossRef
  4. A. Onodera, Ferroelectrics. 267, 131 (2002);
    CrossRef
  5. V. V. Gafiychuk, B. K. Ostafiychuk, D. I. Popovych, I. D. Popovych, A. S. Serednytski, Appl. Surf. Sci. 257, 8396 (2011);
    CrossRef
  6. Y. W. Heo et al., Appl. Phys. Lett. 81, 3046 (2002);
    CrossRef
  7. V. M. Zhyrovetsky et al., Nanoscale Res. Lett.12, 132 (2017);
    CrossRef
  8. B. Wang, S. Nagase, J. Zhao, G. Wang, Nanotechnology. 18(34), 345706 (2007);
    CrossRef
  9. A. A. Peyghan, M. Noei, Physica B. 432, 105-110 (2014);
    CrossRef
  10. S. Haffad, G. Cicero, M. Samah, Energy Procedia. 10, 128 (2011);
    CrossRef
  11. Y. Bobitski, B. Kotlyarchuk, D. Popovych, V. Savchuk, Proc. SPIE 4425, 342-346 (2001);
    CrossRef
  12. B. Kovalyuk et al., Phys. Status Solidi C 10, 1288 (2013);
    CrossRef
  13. J. G. Lu, P. Chang, Z. Fan, Mater. Sci. Engin. R: Rep. 52, 49 (2006);
    CrossRef
  14. R. V. Bovhyra, V. M. Zhyrovetsky, D. I. Popovych, S. S. Savka, A. S. Serednytsky, Sci. Innov. 12, 59 (2016);
    CrossRef
  15. M. Lannoo, J. Bourgoin, Point Defects in Semiconductors I: Theoretical Aspects (Springer, Berlin, 1981).
  16. M. D. McCluskey, Semicond. Semimet. 91, 279 (2015);
    CrossRef
  17. A. A. Peyghan, S. P. Laeen, S. A. Aslanzadeh, M. Moradi, Thin Solid Films 556, 566 (2014);
    CrossRef
  18. S. S. Savka, D. I. Popovych, A. S. Serednytski , NANO 2016: Nanophysics, Nanomaterials, Interface Studies, and Applications. Springer Proceedings in Physics, 195 (Springer, Cham, 2017);
    CrossRef
  19. C. G. Van de Walle, Phys. Rev. Lett. 85, 1012 (2000);
    CrossRef
  20. E-C. Lee , Y-S. Kim, Y-G.Jin, K. J. Chang, Phys. Rev. B 64, 085120 (2001);
    CrossRef
  21. P. Erhart, K. Albe, Phys. Rev. B 70, 115207 (2006);
    CrossRef
  22. T. R. Paudel, W. R. L. Lambrecht, Phys. Rev. B 77, 205202 (2008);
    CrossRef
  23. S. Lany, A. Zunger, Phys. Rev. Lett. 98, 045501 (2007);
    CrossRef
  24. M. K. Yaakob et al., Integr. Ferroelectr. 70, 15 (2014);
    CrossRef
  25. P. Erhart, A. Klein, K. Albe, Phys. Rev. B 72, 085213 (2005);
    CrossRef
  26. Q. Fan, J. Yang, Y. Yu, J. Zhang, J. Cao, Chem. Engin. Transact. 46, 985 (2015);
    CrossRef
  27. O. V. Bovgyra, R. V. Bovgyra, M. V. Kovalenko, D. І. Popovych, А. S. Serednytski, J. Nano-Electron. Phys. 5, 01027 (2013).
  28. O. V. Bovgyra, R. V. Bovgyra, D. І. Popovych, А. S. Serednytski, J. Nano-Electron. Phys. 7(4), 04090 (2015).
  29. J. Andzelm, D. King-Smith, G. Fitzgerald , Chem. Phys. Lett. 335, 321 (2001);
    CrossRef
  30. J. P. Perdew, K. Burke, M. Ernzerhof, Phys. Rev. Lett. 77, 3865 (1996);
    CrossRef
  31. H. J. Monkhorst, J. D. Pack, Phys. Rev. B 13, 5188 (1976);
    CrossRef
  32. F. Oba, M. Choi, A.Togo, I. Tanaka, Sci. Technol. Adv. Mater. 12, 034302 (2011);
    CrossRef
  33. R. Bovhyra, D. Popovych, O. Bovgyra, A. Serednytski, Nanoscale Res. Lett. 12, 76 (2017);
    CrossRef