Hostname: page-component-7bb8b95d7b-qxsvm Total loading time: 0 Render date: 2024-09-25T12:14:15.191Z Has data issue: false hasContentIssue false
  • English
  • Français

Improved Low Resistance Contacts of Ni/Au and Pd/Au to P-Type GaN Using a Cryogenic Treatment

Published online by Cambridge University Press:  03 September 2012

Mi-Ran Park ,
Wayne A. Anderson  and
Seong-Ju Park
Mi-Ran Park
Affiliation:
State University of New York at Buffalo, Department of Electrical Engineering, Amherst, NY, U.S.A.
Wayne A. Anderson
Affiliation:
State University of New York at Buffalo, Department of Electrical Engineering, Amherst, NY, U.S.A.
Seong-Ju Park
Affiliation:
Kwangju Institute of Science and Technology, Department of Materials Science and Engineering, Kwangju, Korea
Get access

Abstract

A low resistance Ohmic contact to p-type GaN is essential for reliable operation of electronic and optoelectronic devices. Such contacts have been made using Ni/Au and Pd / Au contacts to p-type Mg-doped GaN (1.41×1017 cm−3) grown by metalorganic chemical vapor deposition ( MOCVD ) on ( 0001 ) sapphire substrates. Thermal evaporation was used for the deposition of those metals followed by annealing at temperatures of 400 ∼ 700 °C in an oxygen and nitrogen mixed gas ambient, then subsequently cooled in liquid nitrogen which reduced the specific contact resistance from the range of 9.46∼2.80×10−2 ωcm2 to 9.84∼2.65×10−4 ωcm2 for Ni/Au and from the range of 8.35∼5.01×10−4 ωcm2 to 3.34∼1.80×10−4 ωcm2 for Pd/Au. The electrical characteristics for the contacts were examined by the current versus voltage curves and the specific contact resistance was determined by use of the circular transmission line method (c-TLM). The effects of the cryogenic process on improving Ohmic behavior (I-V linearity) and reducing the specific contact resistance will be discussed from a microstructural analysis which reveals the metallurgy of Ohmic contact formation.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 595: Symposium W – GaN and Related Alloys - 1999 , 1999 , F99W11.77
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., Senoh, M., Iwasa, N., and Nagahama, S., Jpn. J. Appl. Phys. 34, L797(1995).Google Scholar
2. Nakamura, S., Senoh, M., Iwasa, N., Nagahama, S., Yamada, T., and Mukai, T., Jpn. J. Appl. Phys. 34, L1332(1995).Google Scholar
3. Nakamura, S., and Senoh, M., Jpn. J. Appl. Phys. 30, L1998(1991).Google Scholar
4. Nakamura, S., Senoh, M., Nagahama, S., Iwasa, N., Yamada, T., Matsushita, T., Kiyoku, H., and Sugimoto, Y., Jpn. J. Appl. Phys. 35, L217(1996).Google Scholar
5. Holloway, P. H., Kim, T-J., Trexler, J. T., Miller, S., Fijol, J. J., Lampert, W. V., Haas, T. W., Appl. Sur. Sci., 117/118, 362(1997).Google Scholar
6. Koide, Y., Maeda, T., Kawakami, T., Fujita, S., Uemura, T., Shibata, N., and Murakami, M., J. Elec, Mat., V28. 341(1999).Google Scholar
7. Trexler, J. T., Pearton, S. J., Holloway, P. H., Mier, M. G., Evans, K. R., and Karlicek, R. F., Mat. Res. Soc. Symp. Proc., V449, 1091(1997).Google Scholar
8. Kim, T., Khim, J., Chae, S., and Kim, T., Mat. Res. Soc. Symp. Proc., V468, 427(1997).Google Scholar
9. Kim, J. K. and Lee, J., Appl. Phy. Lett., 73, 2953(1998).Google Scholar
10. Rhoderick, E. H. and Williams, R. H., “Metal-Semiconductor contacts”, Clarendon, 2nd, P206(1988).Google Scholar
11. Venugopalan, H. S., Mohney, S. E., Luther, B. P., Delucca, J. M., Walter, S. D., Redwing, J. M., and Bulman, G. E., Mat. Res. Soc. Symp. Proc., V468, 431(1997).Google Scholar
12. Trexler, J. T., Miller, S. J., Holloway, P. H., Kwan, M. A., Mat. Res. Soc. Symp. Proc., V395, 819(1996).Google Scholar
13. Brandes, E. A., “Smithells Metals Reference Book”, Batterworths, 6th Ed. Google Scholar
14. Duxstad, K. J., Haller, E. E., Yu, K. M., Hirsch, M. T., Imler, W. R., Steigerwald, D. A., Ponce, F. A., and Romano, L. T., Mat. Res. Soc. Symp. Proc., V449, 1049(1997).Google Scholar