Hostname: page-component-76fb5796d-r6qrq Total loading time: 0 Render date: 2024-04-25T12:57:47.705Z Has data issue: false hasContentIssue false
  • English
  • Français

Low Au Content Ohmic Contacts to n-GaAs Incorporating Sputtered Tungsten Oxide

Published online by Cambridge University Press:  25 February 2011

Naftali Lustig ,
R. G. Schad  and
A. Fleischman
Naftali Lustig
Affiliation:
IBM General Technology Division, Hopewell Junction, New York. 12533
R. G. Schad
Affiliation:
IBM, T. J. Watson Research Center, Yorktown Heights, New York 10598
A. Fleischman
Affiliation:
IBM General Technology Division, Hopewell Junction, New York. 12533
Get access

Abstract

Electron-beam (e-beam) evaporated low Au content NiGe(Au)W ohmic contacts with a contact resistance (Rc) as low as 0.15 Ω-mra have been reported. Due to the high melting point of W it is desirable to deposit this layer by means other than e-beam evaporation. However, the use of nearly oxygen-free sputtered W, yields contact resistances in excess of 0.7 Ω-mm. By replacing the sputtered W by a reactively sputtered metallic W oxide, containing ∼25 at. % oxygen, the low contact resistance (Rc < 0.15 Ω-mm) is restored. Contacts employing a reactively sputtered W nitride in place of W oxide also yield high Rc's (∼0.75 Ω-mm). Auger depth profiles of the reacted contacts show a significant outdiffusion of Ga from the GaAs substrate in the presence the oxygenated W but not in the low oxygen and the W nitride contacts. These results and the fact that our previously reported e-beam evaporated W contacts also contain ∼25 at. % oxygen, suggest an oxygen assisted ohmic contact formation mechanism.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 260: Symposium C – Advanced Metallization and Processing for Semiconductor Devices and Circuits , 1992 , 493
Copyright
Copyright © Materials Research Society 1992

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. Fricke, K., Hartnagel, H. L., Schutz, R., Schweeger, G. and Wurfl, J., IEEE Elect. Dev. Lett. 10, 577 (1989).CrossRefGoogle Scholar
2. Lustig, N., Murakami, M., Norcott, M. and McGann, K., Appl. Phys. Let. 58, 2093 (1991).Google Scholar
3. Lustig, N., J. Vac. Science and Tech. B, May/June (1992).Google Scholar
4. Lustig, N. and Schad, R., App. Phys. Lett. 60, 1984 (1992).Google Scholar
5. Mario, G. S. and Das, M. B., Solid State Electron. 25, 91 (1982).Google Scholar
6. Kuriyama, Y. and Ohfuji, S., J. Appl. Phys. 66, 2446 (1989).Google Scholar
7. Basavaiah, S. and Pollack, S. R., App, J.. Phys. 39, 5548 (1968).Google Scholar
8. Kubaschewski, O. and Alcock, C. B., Metallurgical Thermochemistry, 5th ed. (Pergamon, Oxford 1979).Google Scholar
9. Holloway, P. H. and Nelson, C. C., Thin Solid Films, 35, L13 (1976).Google Scholar
10. Murakami, M., Lustig, N., Price, W. and Fleischman, A., Appl. Phys. Lett. 59, 2409 (1991).Google Scholar