Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-29T07:46:57.769Z Has data issue: false hasContentIssue false

Electrical Characterization of Sputter Deposition Induced Defects in n-GaN

Published online by Cambridge University Press:  15 February 2011

F. D. Auret
Affiliation:
Department of Physics, University of Pretoria, Pretoria 0002, South Africa
S. A. Goodman
Affiliation:
Department of Physics, University of Pretoria, Pretoria 0002, South Africa
F. K. Koschnick
Affiliation:
Department of Physics, University of Pretoria, Pretoria 0002, South Africa CRHEA-CNRS, Valbonne, France.
J.-M. Spaeth
Affiliation:
CRHEA-CNRS, Valbonne, France.
B. Beaumont
Affiliation:
CRHEA-CNRS, Valbonne, France.
P. Gibart
Affiliation:
CRHEA-CNRS, Valbonne, France.
Get access

Abstract

We have used current-voltage (I-V) measurements to assess and compare the electrical characteristics of resistively evaporated and sputter deposited Au Schottky contacts on epitaxially grown GaN. These I-V measurements revealed that resistively deposited Au contacts exhibited excellent rectification properties: high barrier height, low reverse current and good ideality factor (n = 1.04). In contrast, sputter deposited contacts had poor characteristics: low barrier height, high reverse current and non-linear forward I-V characteristics. The cause of this is thought to be defects introduced at and near the surface during sputter deposition. Deep level transient spectroscopy (DLTS) showed that at least four defects, with energy levels at 0.22±0.02 eV, 0.30±0.01 eV, 0.40±0.01 eV and 0.45±0.10 eV below the conduction band, were introduced in the GaN during sputter deposition. The first of these defects has similar electronic properties as a radiation induced defect in GaN, speculated to be the nitrogen vacancy, while the second appears to be the same as a defect in the as-grown material. The latter two defects have not previously been observed in as-grown or processed epitaxial GaN.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

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

[1] Nakamura, S. and Fasol, G., in “The blue laser diode”, (Springer Verlag, 1997).Google Scholar
[2] Doverspike, K., Wickenden, A. E., Binarii, S. C., Gaskill, D. K. and Freitas, J. A., Mat. Res. Soc. Symp. Proc. Vol. 395, p897 (1996).Google Scholar
[3] Maissel, L. I.: in “Handbook of thin film technology”, (ed. Maissel, L. I. and Glan, R.), 14; 1970, New York, McGraw-Hill.Google Scholar
[4] Mullins, F. H. and Brunnschweiler, A., Solid State Electron. 19, 47 (1976).Google Scholar
[5] Grussell, E., Berg, S. and Andersson, L. P., J. Electrochem. Soc. 127, 1573 (1980).Google Scholar
[6] Vanderbroucke, D. A., Mierhaegte, R. L. van, Lafrere, W. H. and Cardon, F., Semicond. Sci. Technol. 2, 293 (1987).Google Scholar
[7] Fonash, S. J., Ashok, S. and Singh, R., Appl. Phys. Lett. 39, 423 (1981).Google Scholar
[8] Auret, F. D., Goodman, S. A., Leclerc, Y., Myburg, G. and Schutte, C., Materials Science and Technology 13, 945 (1997).Google Scholar
[9] Lang, D. V., J. Appl. Phys. 45, 3023 (1974).Google Scholar
[10] Hacke, P., Detchprohm, T., Hiramatsu, K. and Sawaki, N., Appl. Phys. Lett. 63, 2676, (1993).Google Scholar
[11] Ruvimov, S., Liliental-Weber, Z., Washburn, J., Duxstad, K. J., Hailer, E. E., Fan, Z.-F., Mohammed, S. N., Kim, W., Botchkarev, A. E. and Morkoc, H., Appl. Phys. Lett. 69, 1556, (1996).Google Scholar
[12] Hacke, P., Detchprohm, T., Hiramatsu, K., Sawaki, N., Tadatomo, K. and Miyake, K., J. Appl. Phys. 76, 304 (1994).Google Scholar
[13] Gotz, W., Johnson, N. M., Amano, H. and Akasaki, I., Appl. Phys. Lett. 65, 463 (1994).Google Scholar
[14] Ma, Q. Y., Schmidt, M. T., Wu, X., Evans, H. L. and Yang, E. S., J. Appl. Phys. 64, 2469 (1988).Google Scholar
[15] Auret, F. D., Goodman, S. A., Koschnick, F. K., Spaeth, J.-M., Beaumont, B. and Gibart, P., Appl. Phys. Lett. (L986265), January 18, 1999.Google Scholar
[16] Fang, Z-Q., Look, D. C., Kim, W., Fan, Z., Botchkarev, A. and Morkoc, H., Appl. Phys. Lett. 72, 2277 (1998).Google Scholar
[17] Haase, D., Schmid, M., Kürner, W., Dörnen, A., Häirle, V., Scholtz, F., Burkard, M. and Schweitzer, H., Appl. Phys. Lett. 69, 2525 (1996).Google Scholar
[18] Auret, F. D., Myburg, G., Goodman, S. A., Bredell, L. J. and Barnard, W. O., Nucl. Instr. and Meth. in Phys. Res. B67, 411 (1992).Google Scholar