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




rubrene, Alq3, oxidized rubrene, vacuum deposition, thin films, FTIR spectra, photoluminescence


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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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



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