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Dimerization on GaN(001) Surfaces

Published online by Cambridge University Press:  01 January 1992

Min-Hsiung Tsai
Affiliation:
Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287-1504, U.S.A.
John D. Dow
Affiliation:
Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85287-1504, U.S.A.
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Abstract

The GaN(OOl) surface is polar with either N- or Ga-termination. We predict that the Ga-terminated surface does not dimerize, but instead the surface Ga atoms relax into the vacuum by about ≈0.38 Å. The N-terminated surface is predicted to form a c(2×4) structure with N2 dimers in rows of length two. This is to be contrasted with the (2×1) Si(001) surface, on which the dimer rows are infinitely long, and with the (2×4) GaAs(OO1) surface, on which the rows are three dimers long.

Type
Research Article
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

1 Strite, S., Ruan, J., Li, Z., Salvador, A., Chen, H., Smith, D. J., Choyke, W. J., and Morkoc, H., J. Vac. Sci. Technol. B 9, 1924 (1991).Google Scholar
2 Lei, T., Fanciulli, M., Molnar, R. J., Moustakas, T. D., Graham, R. J., and Scanlon, J., Appl. Phys. Lett. 59, 944 (1991).Google Scholar
3 Hiramatsu, K., Amano, H., Akasaki, I., Kato, H., Koide, N., and Manabe, K., J. Crystal Growth 107, 509 (1991).Google Scholar
4 Akasaki, I., Amano, H., Kito, M., and Hiramatsu, K., Luminescence, J. 48&49, 666 (1991).Google Scholar
5 Kohn, W. and Sham, L. J., Phys. Rev. 140, 1133 (1965); Ceperly, D. M. and Alder, G. J., Phys. Rev. Lett. 45, 566 (1980).Google Scholar
6 Sankey, O. F. and Niklewski, D. J., Phys. Rev. B 40, 3979 (1989).Google Scholar
7 Tsai, M.-H., Sankey, O. F., and Dow, J. D., Phys. Rev. B 46, 10464 (1992).Google Scholar
8 Ewald, P. P., Ann. Physik (4) 64, 253 (1921); Göttinger Nachr. Math.-Phys. KL II 3, 55 (1937).Google Scholar
9 Deb, B. M., Rev. Mod. Phys. 45, 22 (1973); Hellmann, H., Einführung in die Quantenchemie,(Franz Deutsche, Leipzig, 1937); Feynman, R. P., Phys. Rev. 56, 340 (1939).Google Scholar
10 Gear, C. W., Argonne National Laboratory Report No. ANL-7126 (1966).Google Scholar
11 Lee, Y. H., Ph.D. dissertation, Kent State University, August, 1986.Google Scholar
12 Tsai, M.-H., Hu, W.-M., Dow, J. D., and Sankey, O. F., J. Vac. Sci. Technol. A 10, 2511 (1992).Google Scholar
13 Tong, S. Y., Lubinsky, A. R., Mrstik, B. J., and Van Hove, M. A., Phys. Rev. B 17, 3303 (1978); Chadi, D. J., Phys. Rev. B 18, 1800 (1978); Chadi, D. J., Phys. Rev. 19, 2074 (1979); Kasowski, R. V., Tsai, M.-H., and Dow, J. D., J. Vac. Sci. Technol., B 5, 953 (1987); Tsai, M.-H., Dow, J. D., Wang, R.-P., and Kasowski, R. V., Phys. Rev. B 40, 9818 (1989); Superlatt. Microstruct. 6, 431 (1989); Alves, J. L. A., Hebenstreit, J., and Schemer, M., Phys. Rev. B 44, 6188 (1991). For low-energy positron diffraction data supporting an ionicity-dependent rotation angle, see Chen, X. M., Brandes, G. R., Canter, K. F., Duke, C. B., Paton, D., Ford, W. K., and Lessor, D. L., Bull. Amer. Phys. Soc. 37, 167 (1992).Google Scholar
14 Packard, W. E., Dai, N.,Dow, J. D., Jaklevic, R. C., Kaiser, W. J., and Tang, S.-L., J. Vac. Sci. Technol. A 8, 3512 (1990).Google Scholar
15 Tsai, M.-H. and Dow, J. D., unpublished.Google Scholar
16 Pashley, M. D., Haberern, K. W., and Gaines, J. M., J. Vac. Sci. Technol. B 9, 938 (1991). The model presented in this paper proposes unreconstructed regions where we have anti-dimers, but it appears that the data lack the necessary resolution to distinguish between these two nearly identical models.Google Scholar
17 Tsai, M.-H. and Dow, J. D., unpublished.Google Scholar
18 The measured bond-length of GaN is 4.49 Å, but the theory, Ref. [7], predicts a somewhat smaller value of 4.27 Å, likely due to the approximation to the exchange-correlation potential in Ref. [6].Google Scholar
19 Such large bond-length changes are to be expected when there is a change of charge state. See Ref. [20]Google Scholar
20 CRC Handbook of Chemistry and Physics ,edited by Lide, David R., 72nd edition, (Boca Raton, Ann Arbor, Boston, 1991-1992).Google Scholar
21 Tsai, M.-H. and Dow, J. D., unpublished.Google Scholar