Advertisement

Metals and Materials International

, Volume 13, Issue 3, pp 229–234 | Cite as

Properties of iridium-inserted nickel silicides by thermal annealing of the Ni/Ir bilayer on silicon and polysilicon substrates

  • Ohsung Song
  • Kijeong Yoon
Article

Abstract

To improve the thermal stability of the conventional nickel monosilicide, 10 nm-Ni/l nm-Ir/p-Si(100) (or poly-crystalline Si) was thermally annealed using rapid thermal annealing for 40 s at 300–1200°C. The annealed bilayer structure developed into Ni(Ir)Si, and the resulting changes in sheet resistance, microstructure, and composition were investigated using a four-point probe, a scanning electron microscope, a field ion beam, an X-ray diffractometer, and an Auger electron spectroscope. The final thickness of Ni(Ir)Six formed on single crystal silicon was approximately 40 nm, and it maintained a sheet resistance of below 20 ω/sq. during the silicidation annealing at 1200°C. The silicide formed on polysilicon had a thickness of 55 nm, and its low resistance was maintained up to 850°C. An additional annealing of silicides at 900°C for 30 min. resulted in a drastic increase in sheet resistance. A possible reason for the improved thermal stability of the silicides formed on single crystal silicion substrate is the role of iridium in preventing NiSi2 transformation. Iridium also improved the thermal stability of the silicides formed on the polysilicon gate, but this enhancement was lessened due to the formation of NiIrSix and also as a result of silicon mixing during high temperature diffusion. In conclusion, the proposed iridium-inserted nickel silicides may be superior to the conventional nickel monosilicides due to improved thermal stability.

Keywords

silicide nickel Ni silicides iridium addition bilayer structure thermal stability 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    R. Lindsay, A. Lauwers, M. de Potter, N. Roelandts, C. Vrancken, and K. Maex,Microelectron. Eng. 55, 157 (2001).CrossRefGoogle Scholar
  2. 2.
    International Technology Road Map for Semiconductor, 2003 ed., p. 25, SIA, Front End Process (2003).Google Scholar
  3. 3.
    E. G. Colgan, J. P. Gambino, and Q. Z. Hong,Mater. Sci. Eng. 16, 43 (1996).CrossRefGoogle Scholar
  4. 4.
    J. Prokop, C. E. Zybill, and S. Veprek,Thin Solid Films 359, 39 (2000).CrossRefADSGoogle Scholar
  5. 5.
    C. Detavernier, R. L. van Meirhaeghe, and F. Cardon,J. Appl. Phys. 88, 133 (2000).CrossRefADSGoogle Scholar
  6. 6.
    Hua. Fang, Mehmet C. Ozturk, E. G. Seebauer, and D. E. Batchelor,J. Electrochem. Soc. 146, 4240 (1999).CrossRefGoogle Scholar
  7. 7.
    J. Lutze, G. Scott, and M. Manley,IEEE Electron Device Lett. 21, 155 (2000).CrossRefADSGoogle Scholar
  8. 8.
    J. B. Lasky, J. S. Nakos, O. J. Cain, and P. J. Geiss,IEEE. Trans. Electron Devices 38, 262 (1991).CrossRefADSGoogle Scholar
  9. 9.
    B. A. Julies, D. Knoesen, R. Pretorius, and D. Adams,Thin Solids Films 347, 201 (1999).CrossRefADSGoogle Scholar
  10. 10.
    M. C. Poon, C. H. Ho, F. Deng, S. S. Lau, and H. Wong,Microelectronics Reliability 38, 1495 (1998).CrossRefGoogle Scholar
  11. 11.
    C. Lavoie, F. M. d'Heurle, C. Detavemier, and C. Cabral Jr.,Microelectronic Engineering 70, 144 (2003).CrossRefGoogle Scholar
  12. 12.
    S. H. Cheong and O. S. Song,Kor. J. Mater. Res. 13, 279 (2003).Google Scholar
  13. 13.
    W. Huang, L. C. Zhang, Y. Z. Gao, and H. Y. Jin,Micro-electronic Engineering 83, 345 (2006).CrossRefGoogle Scholar
  14. 14.
    A. Lauwers, A. Steegen, M. de-Potter, R. Lindsay, A. Satta, H. Bender, and K. Maex,J. Vac. Sci. Technology B 19, 2026 (2001).CrossRefADSGoogle Scholar
  15. 15.
    D. X. Xu, S. R. Das, J. P. McCaffrey, C. J. Peters, and L. E. Erickson,Mater. Res. Soc. Symp. 402, 59 (1996).Google Scholar
  16. 16.
    M. Y. Wang, C. W. Chang, C. M. Wu, C. T. Lin, C. H. Hsieh, W. S. Shue, and M. S. LiangVLSI Technology Dig., 153 (2003).Google Scholar
  17. 17.
    R. Kurt, W. Pitscheke, A. Heinrich, H. Griesmann, J. Schumann, and K. Wetzig,17th International Conference on Thermoelectrics, p. 249–252, IEEE 98 TH, Nagoya, Japan (1998).Google Scholar

Copyright information

© Springer 2007

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringThe University of SeoulSeoulKorea

Personalised recommendations