Analysis of the characteristics of a white organic LED using the newly synthesized blue material methyl-DPVT by varying the thickness of the DPVBi layer

作者：Oh HS^*; Cho JY; Yoon SB

来源：Journal of the Korean Physical Society, 2004, 45(2): 460-464.

• white organic LED (OLED)
• DPVBi
• methyl-DPVT
• quantum efficiency

A two-wavelength type of white organic light-emitting diode (OLED) having a blue/orange emitting layer was fabricated by synthesizing Methyl-DPVT, a new-derivative of the blue-emitting material DPVBi on the market. The white-emission of the two-wavelength type was successfully obtained by representing not only blue emission by using DPVBi but also orange emission by methyl-DPVT as a host material and Rubrene as a guest material. The basic structure of the fabricated white OLED is glass/ITO/NPB(150 Angstrom)/DPVBi/methyl-DPVT:Rubrene [2.0 wt%] (100 Angstrom)/BCP(70 Angstrom)/Alq(3)(150 Angstrom)/AI(600 Angstrom). To evaluate the characteristics of the devices, we varied the thickness of the DPVBi layer from 100 Angstrom to 80 Angstrom to 60 Angstrom. A nearly pure white-emission was obtained in CIE coordinates of (0.3327, 0.3397) when the DPVBi layer was 60-Angstrom thick at an applied voltage of 11 V. The device started to operate at 1 V and to emit light at 2.5 V. The external quantum efficiency was above 0.5% both when almost all of the current was injected and the applied voltage was over 10 V. A superior maximum quantum efficiency 0.746%, was obtained at an applied voltage of 18.5 V.

• 出版日期2004-8