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Abstract. This paper describes changes in current-voltage (I-V) characteristic of an organic light-emitting device (OLED) stacked as a multilayer of ITO/MEH-PPV/Alq3/Al. The ordered, stacked ITO/MEH-PPV/Alq3/Al multi-layers were fabricated by spin-coating and thermal vacuum evaporation methods. First, dissolved MEH-PPV solution was spin-coated on ITO-electrodes that had been covered on a glass-slide. Subsequently, an Alq3 layer was evaporated thermally on the MEH-PPV-coated layer. Finally, an Al-electrode was evaporated also on the electron transport layer. UV-vis absorption and photoluminescent characterization of the MEH-PPV and Alq3 layer as well as their surface images were performed. All spectra obtained revealed the MEH-PPV and Alq3 were deposited as given structure. The I-V characteristics show the present of the Alq3-electron transport layer deposited between the MEH-PPV emissive layer and Al-cathode could enhance current-voltage characteristic reducing the threshold voltage and turn-on voltage.
Keywords: UV-vis absorption, photoluminescence, electron transport layer, current-voltage characteristics.
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