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Investigation of Aluminum and Titanium/Aluminum Contacts to n-Type Gallium Nitride

Published online by Cambridge University Press:  10 February 2011

B. P. Luther ,
S. E. Mohney ,
T. N. Jackson ,
M. Asif Khan ,
Q. Chen  and
J. W. Yang
B. P. Luther
Affiliation:
Department of Electrical Engineering, The Pennsylvania State University, University Park, PA 16802
S. E. Mohney
Affiliation:
Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, mohney@ems.psu.edu
T. N. Jackson
Affiliation:
Department of Electrical Engineering, The Pennsylvania State University, University Park, PA 16802
M. Asif Khan
Affiliation:
APA Optics, Inc., 2950 N.E. 84th Lane, Blaine, MN 55449
Q. Chen
Affiliation:
APA Optics, Inc., 2950 N.E. 84th Lane, Blaine, MN 55449
J. W. Yang
Affiliation:
APA Optics, Inc., 2950 N.E. 84th Lane, Blaine, MN 55449
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Abstract

We report on a study of Al and Ti/Al contacts to n-type GaN. Al contacts on n-GaN (7 x l017cm-3) annealed in forming gas at 600°C reached a minimum contact resistivity of 8x10~6Qcm2 and had much better thermal stability than reported by previous researchers. Ti/Al (35nm/l 15nm) contacts on n-GaN (5xl0I7cm~3) had resistivities of 7 x l0"6Qcm2 and 5xl0"6Qcm2 after annealing in Ar at 400°C for 5min and 600°C for 15sec, respectively. Depth profiles of Ti/Al contacts annealed at 400°C showed that low contact resistance was only achieved after Al diffused to the GaN interface. We propose that the mechanism for ohmic contact formation in Ti/Al contacts annealed in the 400-600°C range includes reduction of the native oxide on GaN by Ti and formation of an Al-Ti intermetallic phase in intimate contact with the GaN. Contacts with different Ti/Al layer thicknesses were investigated and those with 50nm/100nm layers had the same low resistance and better stability than 25nm/125nm contacts.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 449: Symposium N – III-V Nitrides , 1996 , 1097
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

1. Fan, Z.-F., Mohammad, S. N., Kim, W., Aktas, O., Botchkarev, A. E. and Morkoc, H., Appl. Phys. Lett. 68, 1672 (1996).Google Scholar
2. Lin, M. E., Ma, Z., Huang, F. Y., Fan, Z. F., Allen, L. H., and Morkoc, H., Appl. Phys. Lett. 64, 1003 (1994).Google Scholar
3. Ruvimov, S., Liliental-Weber, Z., Washburn, J., Duxstad, K. J., Haller, E. E., Fan, Z.-F., Mohammad, S. N., Kim, W., Botchkarev, A. E. and Morkoc, H., Appl. Phys. Lett. 69, 1556 (1996).Google Scholar
4. Ping, A. T., Asif Khan, M., and Adesida, I., J. Electron. Mat. 25, 819 (1996).Google Scholar
5. Marlow, G. S. and Das, M. B., Solid St. Electron. 25, 91 (1982).Google Scholar
6. Kowalczyk, S. P., Waldrop, J. R., and Grant, R. W., J. Vac. Sci. Technol. 19, 611 (1981).Google Scholar
7. Boer, K. W., Survey of Semiconductor Physics (Van Nostrand, New York, 1990).Google Scholar
8. Pankove, J. I. and Schade, H., Appl. Phys. Lett. 25, 53 (1971).Google Scholar
9. Foresi, J. S. and Moustakas, T. D., Appl. Phys. Lett. 62, 2859 (1993).Google Scholar
10. Smith, L. L., Davis, R. F., Kim, M. J., Carpenter, R. W. and Huang, Y., J. Mater. Res. 11, 2257 (1996).Google Scholar
11. Binari, S. C., Dietrich, H. B., Kelner, G., Rowland, L. B., Doverspike, K., and Gaskill, D. K., Electron. Lett. 30, 909 (1994).Google Scholar