Study on the Effects of Yb: Ag Alloy Cathode on the Photoelectric Performance of the Top Emitting White Organic Light-emitting Devices
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摘要: 研制了以镱银合金为透明阴极的顶发射白光OLED器件。采用ITO/NPB: LiQ(5%)(10 nm)/TCTA(20 nm)/FIrpic+3.5% Ir(ppy)3+0.5%Ir(MDQ)2(acac)(25 nm)/TPBI(10 nm)/LiF(5 nm)/Yb: Ag (X%)(X nm)器件结构,在相同镱银比例下,蒸镀不同厚度的镱银合金阴极制备了新型顶发射白光OLED器件,获得了优化的镱银合金厚度为12 nm;固定镱银阴极厚度,蒸镀不同比例的镱银合金阴极制备了新型顶发射白光OLED器件,探究不同比例的镱银合金对有机电致发光器件的影响。结果表明,当镱银电极的掺杂比例为10:1时,器件的性能最佳,在20 mA/cm2电流密度下,器件的驱动电压为2.3 V,亮度为1406 cd/m2,色坐标为(0.3407, 0.3922)。
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关键词:
- Yb: Ag合金 /
- 阴极 /
- 顶发射白光OLED微型显示器 /
- 光电特性
Abstract: Top-emitting white organic light-emitting diode(OLED) devices with a Mg: Ag alloy as a transparent cathode were fabricated. Based on the device structure of ITO/NPB: LiQ(5%) (10 nm)/TCTA(20 nm)/FIrpic+3.5% Ir(ppy)3+0.5%Ir(MDQ)2(acac) (25 nm)/TPBI(10 nm)/LiF(5 nm)/Yb: Ag (X%) (X nm), the top-emitting white OLED devices were prepared by using Yb: Ag alloy of different thickness as the cathode at the evaporation ratio of 10:1, the optimum thickness of Yb: Ag cathode was 12 nm by contrasting. The effect of different proportions of Yb: Ag alloy on OLEDs was investigated by changing the doping ratio of Ag. Based on the preliminary results, the alloy with a Ag mass fraction of 10% exhibits good electron injection characteristics, which can effectively improve the light-emitting characteristics of the device. When the current density was 20 mA/cm2, the driving voltage was 2.3 V, the brightness was 1406 cd/m2, and the color coordinates were close to (0.3407, 0.3922).-
Key words:
- Yb: Ag alloy /
- cathode /
- top emitting white OLED /
- photoelectric property
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表 1 不同Yb: Ag阴极厚度下器件的性能参数
Table 1. Performance parameters of the device at various thickness of Yb: Ag
Yb: Ag thickness/nm Voltage/V Luminance/(cd/cm2) CIE(X, Y) 11 4.12 1452 0.3373, 0.3967 12 4.08 1387 0.3263, 0.3943 14 4.06 1293 0.3162, 0.3936 16 4.05 1201 0.3038, 0.3896 20 4.04 1007 0.2812, 0.3810 表 2 不同Yb: Ag掺杂比例的器件性能参数
Table 2. Performance parameters of the device at different Yb : Ag doping ratios
Yb: Ag ratio Voltage/V Luminance/(cd/cm2) CIE(X, Y) 10:0.8 3.99 1459 0.3426, 0.3940 10:1 3.99 1406 0.3407, 0.3922 10:1.5 3.97 1329 0.3325, 0.3901 10:2 3.98 1230 0.3260, 0.3850 -
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