Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-29T07:50:06.106Z Has data issue: false hasContentIssue false
  • English
  • Français

Bulk and Surface Electronic Structure of GaN Measured Using Angle-Resolved Photoemission, Soft X-ray Emission and Soft X-ray Absorption

Published online by Cambridge University Press:  10 February 2011

Kevin E. Smith ,
Sarnjeet S Dhesi ,
Laurent-C. Duda ,
Cristian B Stagarescu ,
J. H. Guo ,
Joseph Nordgren ,
Raj Singh  and
Theodore D Moustakas
Kevin E. Smith
Affiliation:
Department of Physics, Boston University, Boston, MA 02215 author to whom correspondence should be addressed. Electronicmail: [email protected]
Sarnjeet S Dhesi
Affiliation:
Department of Physics, Boston University, Boston, MA 02215
Laurent-C. Duda
Affiliation:
Department of Physics, Boston University, Boston, MA 02215
Cristian B Stagarescu
Affiliation:
Department of Physics, Boston University, Boston, MA 02215 On leave from the Institute of Microtechnology, Bucharest, Romania.
J. H. Guo
Affiliation:
Department of Physics, Uppsala University, Uppsala, Sweden
Joseph Nordgren
Affiliation:
Department of Physics, Uppsala University, Uppsala, Sweden
Raj Singh
Affiliation:
Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215.
Theodore D Moustakas
Affiliation:
Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215.
Get access

Abstract

The electronic structure of thin film wurtzite GaN has been studied using a combination of angle resolved photoemission, soft x-ray absorption and soft x-ray emission spectroscopies. We have measured the bulk valence and conduction band partial density of states by recording Ga L- and N K- x-ray emission and absorption spectra. We compare the x-ray spectra to a recent ab initio calculation and find good overall agreement. The x-ray emission spectra reveal that the top of the valence band is dominated by N 2p states, while the x-ray absorption spectra show the bottom of the conduction band as a mixture of Ga 4s and N 2p states, again in good agreement with theory. However, due to strong dipole selection rules we can also identify weak hybridization between Ga 4s- and N 2p-states in the valence band. Furthermore, a component to the N K-emission appears at approximately 19.5 eV below the valence band maximum and can be identified as due to hybridization between N 2p and Ga 3d states. We report preliminary results of a study of the full dispersion of the bulk valence band states along high symmetry directions of the bulk Brillouin zone as measured using angle resolved photoemission. Finally, we tentatively identify a non-dispersive state at the top of the valence band in parts of the Brillouin zone as a surface state.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 449: Symposium N – III-V Nitrides , 1996 , 787
Copyright
Copyright © Materials Research Society 1997

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. Wide Band Gap Semiconductors, MRS Symp. Proc. 242, Ed. Moustakas, T.D., Pankove, J.I., and Hamakawa, Y., (1992); S. Strite and H. Morkoç H, J. Vac. Sci. Technol. B 10, 1237 (1992)Google Scholar
2. See for example: Angle Resolved Photoemission, Ed. Kevan, S.D., Elsevier, Amsterdam, 1991; K.E. Smith and S.D. Kevan, Prog. Solid State Chem. 21, 49 (1991).Google Scholar
3. Paratt, L.G., Rev. Mod. Phys. 31, 616 (1959).Google Scholar
4. Nordgren, J. and Wassdahl, N., Phys. Scr. T31, 103 (1989); J. Nordgren, J. Physique C9, 693 (1987). T.A. Callcott, C.H. Zhang, D.L. Ederer, D.R. Mueller, J.E. Rubensson and E.T. Arakawa, Nuc. Inst. Methods A291, 13 (1990).Google Scholar
5. See for example X-Ray Absorption: Principles, Applications, Techniques of EXAFS, SEXAFS, and XANES, Ed. by Koningsberger, D.C., Prins, R. (Wiley, New York, 1988).Google Scholar
6. Lei, T., Fanciulli, M., Molnar, R.J., Moustakas, T.D., Graham, R.J., and Scanlon, J., App. Phy. Lett. 59, 944(1991).Google Scholar
7. Nordgren, J., Bray, G., Cramm, S., Nyholm, R., Rubensson, J-E., and Wassdahl, N., Rev. Sci. Instrum. 60, 1690 (1989); J. Nordgren and R. Nyholm, Nuc. Inst. Methods, A246, 242 (1986)Google Scholar
8. Kevan, S.D., Rev. Sci. Instrum. 54, 1441 (1983).Google Scholar
9. Bermudez, V.M., Kaplan, R., Khan, M.A. and Kuznia, J.N., Phys. Rev. B 48, 2436 (1993)Google Scholar
10. Stagarescu, C. B., Duda, L.-C., Smith, K.E., Guo, J.H., Nordgren, J., Singh, R. and Moustakas, T.D., Phys. Rev. B 54 (1996) (in press).Google Scholar
11. Xu, Y-N. and Ching, W.Y., Phys. Rev. B48, 4335 (1993).Google Scholar
12. Lambrecht, W. R. L., Rashkeev, S. N., Segall, B., Lawniczak-Jablonska, K., Suski, T., Gullikson, E. M., Underwood, J. H., Perera, R. C. C., Rife, J. C., Grzegory, I., Porowski, S., and Wickenden, D. K., Phys. Rev. B (in press).Google Scholar
13. Lambrecht, W.R.L., Segall, B., Strite, S., Martin, G., Agarwal, A., Morkoc, H., and Rockett, A., Phys. Rev. B 50, 14155 (1994)Google Scholar
14. Dhesi, S.S., Stagarescu, C.B., Smith, K.E., Singh, R. and Moustakas, T.D. (unpublished).Google Scholar
15. Ding, S.A., Neuhold, G., Weaver, J.H., Häberle, P., Horn, K., Brandt, O., Yang, H., and Ploog, K., J. Vac. Sci. Technol. A 13, 819 (1996).Google Scholar
16. Rubio, A., Corkill, J.L., Cohen, M.L., Shirley, EX., and Louie, S.G., Phys. Rev. B 48, 11810 (1993).Google Scholar
17. Bermudez, V.M., J. Appl. Phys. 1996.Google Scholar