Optical Properties and Stability of Bilayer Rubrene-Alq3 Films Fabricated by Vacuum Deposition

  • T. Gavrilko Institute of Physics, Nat. Acad. of Sci. of Ukraine
  • V. Nechytaylo Institute of Physics, Nat. Acad. of Sci. of Ukraine
  • L. Viduta Institute of Physics, Nat. Acad. of Sci. of Ukraine
  • J. Baran Institute of Low Temperatures and Structure Research, PAN
Keywords: rubrene, Alq3, oxidized rubrene, vacuum deposition, thin films, FTIR spectra, photoluminescence

Abstract

We report on the optical and structural characterization of the two-component vacuum deposited (VD) rubrene (Rub)-Alq3 films. As is known, Rub-doped OLED active materials demonstrate both promising electroluminescence and transistor characteristics. However, in terms of operational lifetime, the Rub practical application in basic devices has a few draw-backs related to its chemical instability. Our main attention was focused on the role of the Alq3 coverage and the isomeric transformation of a Rub molecule on its chemical stability in these structures. By monitoring the evolution of PL emission in time, we found that the Rub degradation in Rub-Alq3 films is slower than that in vacuum-deposited Rub layers. These results demonstrate that the deposition of an Alq3 layer can be a way to enhance the stability of Rub to the photo-oxidation in optoelectronic devices. The Rub amorphous film crystallization at elevated temperatures in open air was observed for the first time.

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Published
2018-06-18
How to Cite
Gavrilko, T., Nechytaylo, V., Viduta, L., & Baran, J. (2018). Optical Properties and Stability of Bilayer Rubrene-Alq3 Films Fabricated by Vacuum Deposition. Ukrainian Journal of Physics, 63(4), 362. https://doi.org/10.15407/ujpe63.4.362
Section
Surface physics

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