Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-19T04:23:33.015Z Has data issue: false hasContentIssue false
  • English
  • Français

Determination of surface barrier height and surface state density in GaN films grown on sapphire substrates

Published online by Cambridge University Press:  01 February 2011

Seong-Eun Park ,
Joseph J. Kopanski ,
Youn-Seon Kang ,
Lawrence H. Robins  and
Hyun-Keel Shin
Seong-Eun Park
Affiliation:
Semiconductor Electronics Division, National Institute of Standards and Technology Gaithersburg, MD 20899–8120
Joseph J. Kopanski
Affiliation:
Semiconductor Electronics Division, National Institute of Standards and Technology Gaithersburg, MD 20899–8120
Youn-Seon Kang
Affiliation:
Ceramics Division, National Institute of Standards and Technology Gaithersburg, MD 20899–8520
Lawrence H. Robins
Affiliation:
Ceramics Division, National Institute of Standards and Technology Gaithersburg, MD 20899–8520
Hyun-Keel Shin
Affiliation:
Gwangju Techno Park, LED/LD Packaging Service Center, 958–3 Daechon-dong, Buk-gu, Gwangju 500–706, South Korea
Get access

Abstract

Photoreflectance (PR) modulation spectroscopy was performed to investigate surface properties of GaN films grown on sapphire substrates. From the period of the Franz-Keldysh oscillations, the surface electric field across the GaN space charge region was found to be (197 ± 11) kV/cm, which corresponds to a surface state density of 1.0×1012 cm−2. A surface barrier height of 0.71 eV was determined by fitting the dependence of the PR intensities on pump beam power density. We suggest that a deep level is formed at 2.68 eV above the GaN valence band edge due to the large density of surface states.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 831: Symposium E – GaN, AlN, InN, and Their Alloys , 2004 , E3.2
Copyright
Copyright © Materials Research Society 2005

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. Khan, M. A., Kuznia, J. N., Van Hove, J. M., Pan, N., and Carter, J., Appl. Phys. Lett. 60, 3027 (1992).Google Scholar
2. Redwing, J. M., Tischler, M. A., Flynn, J. S., Elhamri, S., Ahoujja, M., Newrock, R. S., and Mitchel, W. C., Appl. Phys. Lett. 69, 963 (1996).Google Scholar
3. Syrkin, A. L., Andreev, A. N., Lebedev, A. A., Rastegaeva, M. G., and Chelnokov, V. E., J. Appl. Phys. 78, 5511 (1995).Google Scholar
4. Sommerhalter, Ch., Matthes, Th. W., Boneberg, J., Leiderer, P., and Lux-Steiner, M. Ch., J. Vac. Sci. Technol. B 15, 1876 (1997).Google Scholar
5. Chang, G. S., Hwang, W. C., Wang, Y. C., Yang, Z. P., and Hwang, J. S., J. Appl. Phys. 86, 1765 (1999).Google Scholar
6. Zhang, X., Chua, S.-J., Liu, W., and Chong, K.-B., Appl. Phys. Lett. 72, 1890 (1998).Google Scholar
7. Behn, U., Thamm, A., Brandt, O., and Grahn, H. T., J. Appl. Phys. 87, 4315 (2000).Google Scholar
8. Qin, L. H., Zheng, Y. D., Feng, D., Huang, Z. C., and Chen, J. C., J. Appl. Phys. 78, 7424 (1995).Google Scholar
9. Aspnes, D. F., Surf. Sci. 37, 418 (1973).Google Scholar
10. Hsu, T. M., Tien, Y. C., Lu, N. H., Tsai, S. P., Liu, D. G., and Lee, C. P., J. Appl. Phys. 72, 1065 (1992).Google Scholar
11. Liu, W., Li, M. F., Chua, S. J., Akutsu, N., and Matsumoto, K., Semicond. Sci. Technol. 14, 399 (1999).Google Scholar
12. Hecht, M., Phys. Rev. B 41, 7918 (1990).Google Scholar
13. Behn, U., Thamm, A., Brandt, O., and Grahn, H. T., J. Appl. Phys. 90, 5081 (2001).Google Scholar
14. Hovel, H. in Semiconductors and Semimetals (Academic, New York, 1975), Vol. 11, p. 59.Google Scholar
15. Pearton, S. J., Zopler, J. C., Shul, R. J., and Ren, F., J. Appl. Phys. 86, 1 (1999).Google Scholar
16. Yin, X., Chen, H.-M., Pollak, F. H., Chen, Y., Montano, P. H., Kirchner, P. D., Pettit, G. D., and Woodall, J. M., J. Vac. Sci. Technol. A 10, 131 (1992).Google Scholar
17. Koley, G. and Spencer, M. G., J. Appl. Phys. 90, 337 (2001).Google Scholar
18. Simpkins, B. S., Yu, E. T., Waltereit, P., and Speck, J. S., J. Appl. Phys. 94, 1448 (2003).Google Scholar