Influence of Different Atmospheres on the Life Time of Porous Silicon Light-Emitting Devices


In present report, we investigated the degradation processes in porous silicon light-emitting devices (LED) in different atmospheres (O2, N2, air and vacuum) by photoluminescence (PL), electroluminescence (EL), lifetime (LT) and I-V characteristic measurements as well as by Energy Dispersive X-ray Spectroscopy (EDS). The contacts were made by evaporation of Au and Au/Cu alloy. The LEDs emit in visible range at forward and reverse bias. As a rule, full width at half maximum of EL spectrum is wider than that of PL spectrum. The bias direction of applied voltage during degradation change EL, PL, I-V characteristics, and LT of the LEDs. At forward bias, LT degradation is less than that in reverse bias.

The degradation of LEDs during forward bias did not produce any change in the spectral shape of EL and PL. At reverse bias, degradation led to red shift in the peak of EL and PL. The results show that the lifetime of LEDs with Au contact is longer than Au-Cu. Operating in different atmospheres, the LT in vacuum is longest and is more than 100 hours in reverse bias at room temperature.

Possible mechanisms of degradation of LEDs are discussed. It is proposed that degradation is connected mainly with two processes: oxidation and metal diffusion. It is shown that the oxygen and metal in ionic state can diffuse quickly. Hence, in forward bias, the diffusion of metal would dominate, and in reverse bias, diffusion of oxygen dominates.

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


  1. 1.

    F. Kozlowski, P. Steiner, M. Sauter and W. Lang, J. Luminescence, 57, 185 (1993)

    CAS  Article  Google Scholar 

  2. 2.

    D. Dimova-Malinovska, M. Tzolov, N. Tzenov, D. Nesheva. Thin Sol. Films, 297, 285 (1997)

    CAS  Article  Google Scholar 

  3. 3.

    A. Loni, A.J. Simons, T.I. Cox, P.D.J. Calcott, L.T. Canham. Electron. Lett., 31, 1288 (1995)

    CAS  Article  Google Scholar 

  4. 4.

    A.J. Simons, T.I. Cox, A. Loni, L.T. Canham, M.J. Uren, C. Reeves, A.G. Gullis, P.D.J. Calcott, M.R. Houlton, J.P. Newey. In: Advanced Luminescent Materials, ed. By D.J. Lockwood, P.M. Fauchet, N. Koshida and S.R.J. Brueck, PV95-25, (Pennington, NJ, USA, 1996) p. 73.

    Google Scholar 

  5. 5.

    L. Tsybeskov, S.P. Duttagupta, K.D. Hirschman, P.M. Fauchet. Appl. Phys. Lett., 68(15), 2058 (2058)

    Article  Google Scholar 

  6. 6.

    T. Oguro, H. Koyama, T. Ozaki, N. Koshida. J. Appl. Phys., 81(3), 1407 (1407)

    Article  Google Scholar 

  7. 7.

    US Patent., 60/364, 684

  8. 8.

    Ponpon J.P., Siffert P. J. Appl. Phys., 50(7), 5050 (5050)

    Google Scholar 

  9. 9.

    M.A. Lamkin, F.L. Riley and R.J. Fordham, J. Eur. Ceram. Soc., 10, 347 (1992)

    CAS  Article  Google Scholar 

  10. 10.

    J. Zhang and I. Bowl, Appl. Phys. Lett., 71, 2964 (1997)

    CAS  Article  Google Scholar 

  11. 11.

    Y. Jin and K. Chang, Phys. Rev. Lett., 86, 1793 (2001)

    CAS  Article  Google Scholar 

Download references


The support of this work by Hong Kong Baptist University FRG grant is gratefully acknowledged.

Author information



Corresponding author

Correspondence to B.R. Jumayev.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Jumayev, B., Tam, H., Cheah, K. et al. Influence of Different Atmospheres on the Life Time of Porous Silicon Light-Emitting Devices. MRS Online Proceedings Library 737, 814 (2002).

Download citation