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Journal of Electronic Materials

, Volume 26, Issue 3, pp 119–122 | Cite as

Improved Ni ohmic contact on n-type 4H-SiC

  • C. Hallin
  • R. Yakimova
  • B. Pécz
  • A. Georgieva
  • Ts. Marinova
  • L. Kasamakova
  • R. Kakanakov
  • E. Janzén
Article

Abstract

This paper presents the structural, chemical and electronic properties of Al/Ni/ Al-layers evaporated on 4H silicon carbide and then annealed at 1000°C for 5 min. The structure was investigated before and after annealing by transmission electron spectroscopy from cross-sectional specimens. With x-ray photoelectron spectroscopy, both element distribution and bonding energies were followed during sputtering through the alloyed metal-semiconductor contact. Voids are found in both annealed Ni/4H-SiC and Al/Ni/Al/4H-SiC contact layers, though closer to the metal-semiconductor interface in the former case. The first aluminum-layer is believed to prevent voids to be formed at the interface and also to reduce the oxide on the semiconductor surface. The contact was found to be ohmic with a specific contact resistance ρc - 1.8 × 10−5 Ωcm2 which is more than three times lower ρc than for the ordinary Ni/4H-SiC contact prepared in the same way.

Key words

Al/Ni/Al/4H-SiC transmission electron microscopy x-ray photoelectron spectroscopy 

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References

  1. 1.
    J.R. Waldrop and R.W. Grant, Appl. Phys. Lett. 62, 2685 (1993).CrossRefGoogle Scholar
  2. 2.
    H.J. Cho, O.S. Hwang, W. Bang and H.J. Kim, Proc. 5th SiC and Related Material Conf., Washington DC, (1993), p. 663.Google Scholar
  3. 3.
    T.C. Chou, A. Joshi and J. Wadsworth, J. Vac. Sci. Technol. A 9, 1525 (1991).CrossRefGoogle Scholar
  4. 4.
    M.I. Chaudhry, W.B. Berry and M.V. Zeller, Intl. J. Electron- ics 71, 439 (1991).Google Scholar
  5. 5.
    V.M. Bermudez, Appl. Phys. Lett. 42, 70 (1983).CrossRefGoogle Scholar
  6. 6.
    G.L. Harris, G. Keiner and M. Shur, Properties of Silicon Carbide, ed. G.L. Harris, EMIS Datareviews Series, No.13, (INSPEC, 1995).Google Scholar
  7. 7.
    S. Liu, Proc. ICSCRM 95, Kyoto, Japan, (1995), p. 373.Google Scholar
  8. 8.
    R. Kaplan and V.M. Bermudez, Properties of Silicon Carbide, ed, G.L. Harris, EMIS Datareviews Series, No.13, (INSPEC, 1995).Google Scholar
  9. 9.
    E. Kuphal, Solid-State Electron. 24, 69 (1981).CrossRefGoogle Scholar
  10. 10.
    Ts. Marinova, R. Yakimova, V. Krastev, C. Hallin and E. Janzén, J. Vac. Sci. Technol. (in press).Google Scholar
  11. 11.
    C. Hallin, R. Yakimova, V. Krastev, Ts. Marinova and E. Janzén, Proc. ICSCRM 95, Kyoto, Japan, (1995), p. 140.Google Scholar
  12. 12.
    P. Shewmon, Diffusion in Solids, (Warrendale, PA: The Minerals, Metals & Materials Society, 1989).Google Scholar

Copyright information

© The Metallurgical of Society of AIME 1997

Authors and Affiliations

  • C. Hallin
    • 1
  • R. Yakimova
    • 1
  • B. Pécz
    • 2
  • A. Georgieva
    • 3
  • Ts. Marinova
    • 4
  • L. Kasamakova
    • 5
  • R. Kakanakov
    • 5
  • E. Janzén
    • 1
  1. 1.Department of Physics and Measurement TechnologyLinköping UniversityLinköpingSweden
  2. 2.Research Institute for Technical PhysicsBudapestHungary
  3. 3.Faculty of PhysicsSofia UniversitySofiaBulgaria
  4. 4.Institute of General and Inorganic ChemistryBulgarian Academy of SciencesSofiaBulgaria
  5. 5.Institute of Applied PhysicsBulgarian Academy of SciencesPlovdivBulgaria

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