OLED degradation described by using a time-dependent local relaxation model

Abstract

The main mechanisms responsible for the luminance degradation in OLEDs driven under constant current has not yet been identified. In this paper we propose a new approach to describe the intrinsic mechanisms involved in the OLED aging. We will first show that a stretched exponential decay can be used to fit almost all the luminance vs time curves obtained under different driving conditions. In this way we are able to prove that they can all be described by employing a single free parameter model.

By using as an approach based on local relaxation events, we will demonstrate that a single mechanism is responsible for the dominant aging process. Furthermore, we will demonstrate that the main relaxation event is the annihilation of one emissive center.

We will then use our model to fit all the experimental data measured under different driving condition, and show that by carefully fitting the accelerated luminance lifetime-curves, we can extrapolate the low-luminance lifetime needed for real display applications, with a high degree of accuracy.

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References

  1. 1

    I.D. Parker et al, J of App. Phys., 85, 2441, 1999

    CAS  Article  Google Scholar 

  2. 2

    P.E. Burrows et al, App. Phys. Lett., 76, 2493, 2000

    CAS  Article  Google Scholar 

  3. 3

    G.C.M. Silvestre et al, App. Phys. Lett., 78, 1619, 2001

    CAS  Article  Google Scholar 

  4. 4

    H. Aziz and Z.D. Popovic, App. Phys. Lett., 80, 2180, 2002

    CAS  Article  Google Scholar 

  5. 5

    W. E. Howard and O. F. Prache, IBM J. RES. & DEV., 45, 1, 2001

    Article  Google Scholar 

  6. 6

    M. Ishii, R&D Review of Toyota CRDL, 38, 2

  7. 7

    K Trachenko and M. T. Dove, Phys. Rev. B, 70, 132202, 2004

    Article  Google Scholar 

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Correspondence to Benoît Racine.

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Racine, B., Féry, C., Bettinelli, A. et al. OLED degradation described by using a time-dependent local relaxation model. MRS Online Proceedings Library 871, 105 (2005). https://doi.org/10.1557/PROC-871-I10.5

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