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Low-Temperature Self Aligned TiSi2'TiN Bilayer by Rapid Thermal Nitridation of Metastable Titanium Silicide in NH3 Ambient

Published online by Cambridge University Press:  25 February 2011

Ahmad Kermani
Affiliation:
Rapro Technology Inc., Fremont, CA 945381
John Kuehne
Affiliation:
Semiconductor Process and Design Center, Texas Instrument Inc., Dallas, TX 75265
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Abstract

Rapid thermal nitridation (RTN) of metastable Ti silicide in pure ammonia ambient has been shown to result in the formation of a bilayer TiSi 2'TiN structure. This bilayer structure provides an effective self-aligned diffusion barrier against aluminum spiking. Further, the simultaneous formation of TiN on top of the TiSi2 preserves the low resistivity of the silicide layer upon subsequent high temperature process steps. Rutherford backscatttering spectroscopy, Auger electron spectroscopy and four point probe techniques were used to analyze the stoichiometry of the nitrided layer, and to study the kinetics of the nitridation reaction. The nitridation of the metastable silicide film is a substitutional eaction which begins at the surface of the silicide and progresses by substituting nitrogen atoms for silicon. The nitrogen atoms result from dissociation of ammonia The released silicon atoms then diffuse to the silicide'silicon interface and deposit in an epitaxial manner. The benefits of the proposed metallization scheme are substantiated by electrical characterization of the bilayer structure in comparison with a conventional process.

Type
Research Article
Copyright
Copyright © Materials Research Society 1989

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References

REFERENCES

1 - Willemsen, M. F. C. et al., J. Vac. Sci. Technol. B, Vol. 6, 53 1988.Google Scholar
2 - Wittmer, Marc, Appl. Phys. Lett. 52, 1573 1988.Google Scholar
3 - Okamoto, Tatsuo et al., J. Appl. Phys. 62, 4485 1987.Google Scholar
4 - Ku, Y. H. et al., Appl. Phys. Lett. 50, 1598 1987.Google Scholar
5 - Murarka, S. P., J. Vac. Sci. Technol. B2 (4), 693 (1984).Google Scholar
6 - Hara, Tohru et al., IEEE Transaction Electron Devices, Vol. ED–34, 593 1987.Google Scholar
7 - Beyers, Robert and Sinclair, Robert, J. Appl. Phys. 57, 5240 1985.Google Scholar
8 - Wittmer, M., J. vac. Sci. Technol. A2, 273 1984.Google Scholar
9 - Kermani, Almnad et al., Mater. Res. Soc. Symp. Proc. 74, 665 1987.Google Scholar
10 - Kermani, Ahmad et al., International Conference on Ion 6th Implantation Technology Proc. (1986).Google Scholar
11 - Beyers, Robert et al., J. Appl. Phys. 61, 5110 1987.Google Scholar
12 - Kaneko, H. et al., IEEE Trans. Electron Devices ED–33, 1702 1986.Google Scholar
13 - Beyers, Robert et al., J. Vac. sci. Technol. B2, 781 1984.Google Scholar
14 - Iyer, S. S. et al., J. Electrochem. soc. 132, 2240 1985.Google Scholar
15 - Mori, M., IEEE Trans. Electron Devices ED–30, 81 1983.Google Scholar