Temperature Dependent Characteristics of Hydrogenated Amorphous Silicon thin film Transistors

Abstract

The characteristics of inverted staggered hydrogenated amorphous silicon/silicon nitride (a-Si:H/a-SiNx:H) thin film transistors (TFTs) are reported between 80 K and 420 K. The TFTs are found to have three distinct transport regimes. Between 80 K to approximately 260 K, the transport in the TFT channel is dominated by electrons hopping between localized gap states of a-Si:H and is analyzed using Mott’s theory of variable- range hopping. As the tem-perature is increased above ∼260 K the current becomes thermally activated with an activation energy which depends on the gate voltage. The effective field effect mobility, as determined from the TFT characteristics in saturation, is activated in this regime, with an activation energy 0.10 to 0.15 eV. The various activation energies are found to be sensitive to annealing which can be explained by a reduction in deep and shallow states in the a-Si:H active layer. When operated above ∼360 K the TFTs become unstable due to rapid changes in threshold voltage under the applied gate field. The behavior of the threshold voltage is described over the entire temperature range and possible mechanisms are discussed.

This is a preview of subscription content, access via your institution.

References

  1. 1.

    P. Migliorato, Proc. of Eurodisplay, p.44 (1987).

  2. 2.

    R.L. Weisfield, H.C.Tuan, L. Fennell and M.J. Thompson, MRS Symp. Proc. 95, 469 (1987).

    CAS  Article  Google Scholar 

  3. 3.

    M. Bohm, S. Salamon and Z. Kiss, Appl. Phys. A 45, 53 (1988).

    Article  Google Scholar 

  4. 4.

    M.J. Powell, C. van Berkel, I.D. French and D.H. Nicholls, Appl. Phys. Lett. 51, 1242 (1987).

    CAS  Article  Google Scholar 

  5. 5.

    J. Kanicki and P. Wagner, in Silicon Nitride and Silicon Dioxide Thin Insulating Films, eds. VJ. Kapoor and K.T. Hankins, Electrochemical Society, 86–10, 261 (1986).

  6. 6.

    D. Jousse, J. Kanicki, D.T. Kirk and P.M. Lenahan, Appl. Phys. Lett. 52, 445 (1988).

    CAS  Article  Google Scholar 

  7. 7.

    K.D. Mackenzie, A.J. Snell, I. French, P.G. LeComber and W.E. Spear, Appl. Phys. A 31, 87 (1983).

    Article  Google Scholar 

  8. 8.

    T. Tiedje, J.M. Cebulka, D.L. Morel and B. Abeles, Phys. Rev. Lett. 46, 1425 (1981).

    CAS  Article  Google Scholar 

  9. 9.

    N.F. Mott and E.A. Davis in Electronic Processes in Non-Crystalline Materials, Clarendon Press Oxford (1979).

  10. 10.

    M. J. Powell and J. W. Orton, Appl. Phys. Lett. 45, 171 (1984)

    CAS  Article  Google Scholar 

  11. 11.

    M. Shur and M. Hack, J. Appl. Phys. 55, 3831 (1984).

    CAS  Article  Google Scholar 

  12. 12.

    M.J. Powell, Appl. Phys. Lett. 43, 597 (1983).

    CAS  Article  Google Scholar 

  13. 13.

    A.R. Hepburn, J.M. Marshall, C. Main, M. J. Powell and C. van Berkel, Phys. Rev. Lett. 56, 2215 (1986).

    CAS  Article  Google Scholar 

  14. 14.

    R.E.I. Schropp and J. F. Verwey, Appl. Phys. Lett. 50, 185 (1987).

    CAS  Article  Google Scholar 

  15. 15.

    W.B. Jackson and M.D. Moyer, Phys. Rev. B 36, 6217 (1987).

    CAS  Article  Google Scholar 

  16. 16.

    H. Zhang and M. Matsumura, MRS Symp. Proc. 95, 463 (1987).

    CAS  Article  Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to N. Lustig.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Lustig, N., Kanicki, J., Wisnieff, R. et al. Temperature Dependent Characteristics of Hydrogenated Amorphous Silicon thin film Transistors. MRS Online Proceedings Library 118, 267 (1988). https://doi.org/10.1557/PROC-118-267

Download citation