Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-17T14:35:13.378Z Has data issue: false hasContentIssue false
  • English
  • Français

Comparative Study of Defect Properties in GaN: Ab Initio and Empirical Potential Calculations

Published online by Cambridge University Press:  01 February 2011

Fei Gao ,
Eric J. Bylaska ,
Anter El-Azab  and
William J. Weber
Fei Gao
Affiliation:
Pacific Northwest National Laboratory, MS K8–93, P. O. Box 999, Richland, WA 99352, USA
Eric J. Bylaska
Affiliation:
Pacific Northwest National Laboratory, MS K8–93, P. O. Box 999, Richland, WA 99352, USA
Anter El-Azab
Affiliation:
Pacific Northwest National Laboratory, MS K8–93, P. O. Box 999, Richland, WA 99352, USA
William J. Weber
Affiliation:
Pacific Northwest National Laboratory, MS K8–93, P. O. Box 999, Richland, WA 99352, USA
Get access

Abstract

Density functional theory (DFT) is used to study the formation, properties and atomic configurations of monovacancies, antisite defects and possible interstitials in GaN. The relaxation around a vacancy is generally small, but the relaxation around antisite defects is large, particularly for a Ga antisite defect, which is not stable and converts to an N-N<0001> split interstitial. All N interstitials, starting from any possible site, eventually transfer into the N-N split interstitials, forming N2 molecules with one N-N bond, but also some covalent bonds to the surrounding atoms. In the case of Ga interstitials, the most favorable configuration is the Ga octahedral interstitial. However, it is found that the Ga-Ga<1120> split interstitial can bridge the gap between non-bonded Ga atoms along the <1120> direction, which leads to the formation of Ga atomic wires in GaN, with bond distance (2.3Å) close to those noted in bulk Ga. In addition, two representative potentials, namely Stillinger-Weber and Tersoff-Brenner potentials, have been employed to determine the formation of defects using molecular dynamics (MD) method in GaN. The MD results are discussed and compared to DFT calculations. The present DFT and MD results provide guidelines for evaluating the quality and fit of empirical potentials for large-scale simulations of ion-solid interaction and thermal annealing of defects in GaN.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 792: Symposium R – Radiation Effects and Ion Beam Processing of Materials , 2003 , R6.7
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. GaN and related alloys, edited by Pearton, S. J., Kuo, C., Wright, A. F., and Uenoyama, T., (Materials Research Society, Pittsburgh, PA, 1999); Mater. Res. Soc. Symp. Proc. Vol. 537 (1999).Google Scholar
2. Nakamura, S., The Blue Laser Diode-GaN Based Light Emitters and lasers (Springer, Berlin, 1997).Google Scholar
3. Saarinen, K., Suski, T., Grzegory, I., and Look, D. V., Phys. Rev. B 64, 233201 (2001).Google Scholar
4. Chow, K. H., Watkins, G. D., Akira, Usui, and Mizuta, M., Phys. Rev. Lett. 85, 2761 (2000).Google Scholar
5. Bogustawski, P., Briggs, E. L., and Bernholc, J., Phys. Rev. B 51, 17255 (1995).Google Scholar
6. Gorczyca, I., Svane, A., and Christensen, N. E., Phys. Rev. B 60, 8147 (1999).Google Scholar
7. Nord, J., Albe, K., Erhart, P. and Nordlund, K., J. Phys: Condens. Matter 15, 5649 (2003).Google Scholar
8. Vosko, S. H., Wilk, L. and Nusair, M., Can. J. Phys. 58, 1200 (1980).Google Scholar
9. Hamann, D. R., Phys. Rev. B 40, 2980 (1989).Google Scholar
10. Chadi, D. J. and Cohen, M. L., Phys. Rev. B 8, 5747 (1973).Google Scholar
11. Gao, F., Bylaska, E. J., El-Azab, A. L. and Weber, W. J., to be published.Google Scholar
12. Aïchoune, N., Potin, V., Ruterana, P., Hairie, A., Nouet, G. and Paumier, E., Computational Mater. Sci. 17, 380 (2000).Google Scholar
13. Béré, A. and Serra, A., Phys. Rev. B 65, (2001) 205323.Google Scholar
14. Zhang, S. B. and Northrup, J. E., Phys. Rev. Lett. 67, 2339 (1991).Google Scholar
15. Neugebauer, J. and Van de Walle, C. G., Phys. Rev. B 50, 8067 (1994).Google Scholar
16. Mattila, T. and Nieminen, R., Phys. Rev. B 55, 9571 (1997).Google Scholar
17. Boucher, D. E., Deleo, G. G. and Fowler, W. B., Phys. Rev. B 59, 10064 (1999).Google Scholar