Effect of thickness of CuI hole injection layer on properties of organic light emitting diodes


  • Zenon Hotra
  • Pavlo Stakhira
  • Vladyslav Cherpak
  • Dmytro Volynyuk
  • Lesya Voznyak
  • Volodymyr Gorbulyk
  • Bogdan Tsizh




We report the influence of the thickness of a copper iodide (CuI) hole injection layer (HIL) on the performance of organic light-emitting diodes (OLEDs) with tris-8-hydroxyquinoline aluminum (Alq3) active layer and aluminum cathode layer. The investigation of structural and morphological properties of thermally evaporated CuI thin films indicates that they are amorphous. OLEDs with the ITO/CuI/Alq3/poly(ethylene glycol) dimethyl ether/Al structures were fabricated and current density-voltage, luminance-voltage and current efficiency-current density were analyzed. The maximal luminescence current efficiency is obtained for the devices with a CuI thickness of 12nm.

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How to Cite

Z. Hotra, “Effect of thickness of CuI hole injection layer on properties of organic light emitting diodes”, Photonics Lett. Pol., vol. 4, no. 1, pp. pp. 35–37, Mar. 2012.