Low-frequency noise as a diagnostic tool for OLED reliability

P. R F Rocha, L. K J Vandamme, S. C J Meskers, H. L. Gomes, D. M. De Leeuw, P. Van De Weijer

Research output: Chapter in Book/Report/Conference proceedingConference contribution

6 Citations (Scopus)

Abstract

Organic light emitting diodes (OLED), either based on polymers or small molecules, suffer from early failure: an unpredictable sudden increase in current with a total loss of light output. This work addresses this problem using small-signal impedance measurements and electrical noise techniques. Robust OLEDs show a current noise spectrum proportional to 1/f. OLEDs susceptible to failure have 1/f3/2 and/or may start exhibiting a standard 1/f behavior that rapidly evolves with time (typical 30 minutes) to 1/f1.6. In addition OLEDs susceptible to early failure have a higher DC leakage. It is proposed that a combination of both measurements can be used as a diagnostic tool for OLED reliability in a production line. Insight into the physics of the degradation mechanism is also provided. Unreliable OLEDs exhibit current switching events and optical blinks at wavelengths higher than the polymer band gap electroluminescence. It is proposed that degradation is induced by the appearance of an insulating resistive switching layer. Charge recombination trough this layer is responsible for the optical and electrical blinks.

Original languageEnglish
Title of host publication2013 22nd International Conference on Noise and Fluctuations, ICNF 2013
DOIs
Publication statusPublished - 2013
Event2013 22nd International Conference on Noise and Fluctuations, ICNF 2013 - Montpellier, France
Duration: 24 Jun 201328 Jun 2013

Conference

Conference2013 22nd International Conference on Noise and Fluctuations, ICNF 2013
CountryFrance
CityMontpellier
Period24/06/1328/06/13

Keywords

  • diagnostic tool
  • low frequency noise and impedance spectroscopy
  • OLED reliability

ASJC Scopus subject areas

  • Acoustics and Ultrasonics

Fingerprint Dive into the research topics of 'Low-frequency noise as a diagnostic tool for OLED reliability'. Together they form a unique fingerprint.

  • Cite this

    Rocha, P. R. F., Vandamme, L. K. J., Meskers, S. C. J., Gomes, H. L., De Leeuw, D. M., & Van De Weijer, P. (2013). Low-frequency noise as a diagnostic tool for OLED reliability. In 2013 22nd International Conference on Noise and Fluctuations, ICNF 2013 [6578947] https://doi.org/10.1109/ICNF.2013.6578947