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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 24 — Dec. 2, 2013
  • pp: 29558–29566

Analysis of thermal degradation of organic light-emitting diodes with infrared imaging and impedance spectroscopy

Kiyeol Kwak, Kyoungah Cho, and Sangsig Kim  »View Author Affiliations

Optics Express, Vol. 21, Issue 24, pp. 29558-29566 (2013)

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We propose a route to examine the thermal degradation of organic light-emitting diodes (OLEDs) with infrared (IR) imaging and impedance spectroscopy. Four different OLEDs with tris (8-hydroxyquinolinato) aluminum are prepared in this study for the analysis of thermal degradation. Our comparison of the thermal and electrical characteristics of these OLEDs reveals that the real-time temperatures of these OLEDs obtained from the IR images clearly correlate with the electrical properties and lifetimes. The OLED with poor electrical properties shows a fairly high temperature during the operation and a considerably short lifetime. Based on the correlation of the real-time temperature and the performance of the OLEDs, the impedance results suggest different thermal degradation mechanisms for each of the OLEDs. The analysis method suggested in this study will be helpful in developing OLEDs with higher efficiency and longer lifetime.

© 2013 Optical Society of America

OCIS Codes
(120.4630) Instrumentation, measurement, and metrology : Optical inspection
(160.4890) Materials : Organic materials
(230.3670) Optical devices : Light-emitting diodes
(310.6188) Thin films : Spectral properties
(310.6805) Thin films : Theory and design

ToC Category:
Optical Devices

Original Manuscript: June 26, 2013
Revised Manuscript: September 3, 2013
Manuscript Accepted: November 1, 2013
Published: November 21, 2013

Kiyeol Kwak, Kyoungah Cho, and Sangsig Kim, "Analysis of thermal degradation of organic light-emitting diodes with infrared imaging and impedance spectroscopy," Opt. Express 21, 29558-29566 (2013)

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