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The Growth of Tantalum Thin Films by Plasma-Enhanced Atomic Layer Deposition and Diffusion Barrier Properties

Published online by Cambridge University Press:  01 February 2011

H. Kim ,
C. Cabral Jr ,
C. Lavoie  and
S.M. Rossnagel
H. Kim
Affiliation:
IBM Thomas J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598
C. Cabral Jr
Affiliation:
IBM Thomas J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598
C. Lavoie
Affiliation:
IBM Thomas J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598
S.M. Rossnagel
Affiliation:
IBM Thomas J. Watson Research Center, P.O. Box 218, Yorktown Heights, NY 10598
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Abstract

Ta films were grown by plasma-enhanced atomic layer deposition (PE-ALD) at temperatures from room temperature up to 300 °C using TaCl5 as source gas and RF plasma-produced atomic H as the reducing agent. Post-deposition ex situ chemical analyses showed that the main impurity is oxygen, incorporated during the air exposure prior to analysis with typically low Cl concentration below 1 at %. The X-ray diffraction indicates that ALD Ta films are amorphous or composed of nano-grains. The typical resistivity of ALD Ta films was 150-180 μΩ cm, which corresponds to that of β-Ta phase, at a wide range of growth parameters. The conformality of the film is 100 % up to an aspect ratio of 15:1 and 40 % for aspect ratio of 40:1. The thickness per cycle, corresponding to the growth rate, was measured by Rutherford back scattering as a function of various key growth parameters, including TaCl5 and H exposure time and growth temperature. The maximum thickness per cycle values were below 0.1 ML, probably due to the steric hindrance for TaCl5 adsorption. Bilayer structures consisting of Cu films deposited by sputtering and ALD Ta films with various thicknesses were prepared and the diffusion barrier properties of ALD Ta films were investigated by various analysis techniques consisting of X-ray diffraction, elastic light scattering, and resistance analysis. The results were compared with Ta thin films deposited by sputtering with comparable thicknesses. Also, the growth of TaN films by PE-ALD using consecutive exposures of atomic H and activated N2 is presented.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 716: Symposium B – Silicon Materials-Processing, Characterization, and Reliability , 2002 , B8.5
Copyright
Copyright © Materials Research Society 2002

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References

1. Hu, C.-K., and Harper, J.M.E., Mat. Chem. Phys. 51, 5 (1998).Google Scholar
2. Hu, C.-K., Lee, K.Y., Gignac, L., Rossnagel, S.M., Uzoh, C., Chan, K., Roper, P., Harper, J.M.E., Mat. Res. Soc. 514, 287 (1998).Google Scholar
3. Torres, J., Appl. Surf. Sci. 91, 112 (1995).Google Scholar
4. Sze, S.M., Semiconductor Devices, Physics and Technology, Wiley, New York, 1985.Google Scholar
5. Rossnagel, S.M. and Kim, H., 2001 Proceed. International Interconnect Technol. Conf. 3, (2001).Google Scholar
6. Rossnagel, S.M., Sherman, A., and Turner, F., J. Vac. Sci. Technol. B18, 2016 (2000).Google Scholar
7. Kim, H. and Rossnagel, S.M., J. Vac. Sci. Technol. A, in press.Google Scholar
8. Cabral, C. Jr, Lavoie, C., Harper, J.M.E., and Jordan-Sweet, J., Thin Solid Films 397, 194 (2001).Google Scholar
9. Juppo, M., Ritala, M., and Leskela, M., J. Electrochem. Soc. 147, 3377 (2000).Google Scholar
10. Baker, P.N., Thin Solid Films 14, 3 (1972).Google Scholar
11. Goehner, R.P. and Eatough, M.O., Powder diffraction 7, 2 (1992).Google Scholar
12. Phani, A.R. and Santucci, S., Thin Solid Films 396, 1 (2001).Google Scholar
13. Rha, S.-K., Lee, S.-Y., Lee, W.-J., Hwang, Y.-S., Park, C.-O., Kim, D.-W., Lee, Y.-S., and Whang, C.-N., J. Vac. Sci. Technol. B16, 2019 (1998).Google Scholar