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Low Resistance Ohmic Contacts Formation and Mechanism of Current Transport Through p-GaN and p-AlGaN

Published online by Cambridge University Press:  01 February 2011

Indra Chary
Affiliation:
[email protected], Texas Tech University, Nano Tech Center, Lubbock, Texas, United States
Boris Borisov
Affiliation:
[email protected], Texas Tech University, Nano Tech center, Lubbock, Texas, United States
Vladimir Kuryatkov
Affiliation:
[email protected], Texas Tech University, Nano Tech Center, Lubbock, Texas, United States
Yuriy Kudryavtsev
Affiliation:
[email protected], CINVESTAV, Department of Electrical Engineering, Mexico D.F., Mexico
R Asomoza
Affiliation:
[email protected], CINVESTAV, Department of Electrical Engineering, Mexico D.F., Mexico
Sergey A Nikishin
Affiliation:
[email protected], Texas Tech University, Nano Tech Center, Lubbock, Texas, United States
Mark Holtz
Affiliation:
[email protected], Texas Tech University, Nano Tech Center, Lubbock, Texas, United States
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Abstract

We report the influence of surface treatment, annealing temperature and metal bilayer thickness on the specific contact resistance (ρc) of Au/Ni ohmic contacts to p-GaN and p-AlGaN. Ohmic contact on p-GaN with a hole concentration of 6.5 x 1017 cm-3, shows the lowest ρc of ˜9.2 x 10-6 Ω cm2, when GaN was treated in HCl:H2O (3:1) solution before metal deposition and annealed at 500°C for 10 minutes in 90% N2 and 0% O2 atmosphere. Similar procedure applied on p-AlxGa1-xN (x = 5-7%), with a hole concentration of 2.3 x 1017 cm-3, yields a ρc of 1.8 x 10-4 Ω cm2. An increase is observed in ρc when Mg doping exceeds 4 x 1019 cm-3 in both p-GaN and p-AlGaN. This is attributed to Mg self compensation. This increase is more pronounced in AlGaN which we attribute to the presence of residual native aluminum oxides.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

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References

REFERENCES

1. Schubert, E. F., Kim, J. K., Luo, H. and Xi, J-Q, Rep. Prog. Phys. 69, 3069 (2006).Google Scholar
2. Iida, K., Kawashima, T., Miyazaki, A., Kasugai, H., Mishima, S., Honshio, A., Miyake, Y., Iwaya, M., Kamiyama, S., Amano, H. and Akasaki, I., Jpn. J. Appl. Phys. 43, L499 (2004).Google Scholar
3. Yasan, A., McClintock, R., Mayes, K., Shiell, D., Gautero, L., Darvish, S. R., Kung, P. and Razeghi, M., Appl Phys. Lett. 83, 4701 (2003).Google Scholar
4. Allerman, A. A., Crawford, M. H., Fischer, A. J., Bogart, K. H. A., Lee, S. R., Follstaedt, D. M., Provencio, P. P., Koleske, D. D., J. Cryst. Growth. 272, 227 (2004).Google Scholar
5. Kipshidze, G., Kuryatkov, V., Zhu, K., and Borisov, B., Holtz, M., Nikishin, S. and Temkin, H., J. Appl. Phys. 93, 1363 (2003).Google Scholar
6. Rajagopal, P., Roberts, J. C., Cook, J. W. Jr., Brown, J. D., Piner, E. L., and Linthicum., J. Kevin, Mat. Res. Soc. Symp. Proc. 798, Y7.2 (2003).Google Scholar
7. Arulkumaranl, S., Egawa, T., Ishikawa, H., Solid State Electron. 49, 1632 (2005).Google Scholar
8. Kim, J. K., Je, J. H., Lee, J. L., Park, Y. J. and Lee, B. T., J. Electrochem. Soc. 148, 4645 (2000).Google Scholar
9. Khanna, R., Pearton, S. J., Ren, F., Kravchenko, I., Kao, C. J., Chi, G. C., Appl. Surf. Sci. 252, 1826 (2005).Google Scholar
10. Schuette, M.L. and Lu, Wo, J. Vac. Sci. Technol. 23, 3243 (2005).Google Scholar
11. Yun, J. and Choi, K., IEEE Electron Device Lett. 27, 22 (2006).Google Scholar
12. Cha, H. Y., Chen, X., Wu, H., Schaff, W. J., Spencer, M. G. and Eastman, L. F., Electron, J. . Mater. 35, 406 (2006).Google Scholar
13. Wenzel, R., Fischer, G. and Fetzer, R. S., Mat. Sci. Semicond. Process. 4, 367 (2001).Google Scholar
14. Chary, I., Chandolu, A., Borisov, B., Kuryatkov, V., Nikishin, S. and Holtz, M., J. Elec. Materials (To be published).Google Scholar
15. Kipshidze, G., Kuryatkov, V., Borisov, B., Kudryavtsev, Yu., Asomoza, R., Nikishin, S., and Temkin, H., Appl. Phys. Lett. 80, 2910 (2002).Google Scholar
16. Marlow, G. S. and Das, M. B., Solid State Electron., 25, 91 (1982).Google Scholar
17. Ho, J. K., Jong, C. S., Chiu, C. C., Huang, C. N., Shih, K. K., Chen, L. C., Chen, F. R. and Kai, J. J., J. Appl. Phys. 86, 4491 (1999).Google Scholar
18. Hu, C.Y., Ding, Z.B., Qin, Z.X., Chen, Z.Z., Xu, K., Yang, Z.J., Shen, B., Yao, S.D. and Zhang, G.Y., J. Cryst. Growth. 298, 808 (2007).Google Scholar
19. Lim, S.H., Ra, T.Y. and Kim, W.Y., Journal of Electron Microscopy. 52, 459 (2003).Google Scholar
20. Kumakura, K., Makimoto, T. and Kobayashi, N., J. Appl. Phys. 93, 3370 (2003).Google Scholar
21. Blank, T.V. and Gol'dberg, Yu.A., Semiconductors. 4, 1263 (2007) and REFERENCES therein.Google Scholar
22. Chary, I., Kuryatkov, V., Borisov, B., Nikishin, S., and Holtz, M., IEEE Trans. Electron Devices (submitted).Google Scholar