大面積有機發光二極體陽極輔助電極研究

The Research of Auxiliary Anode on Large –Area Organic Light-Emitting Diode

鐘傳億(Chuan-Yi Jhong)

指導教授 ： 蔡裕勝

國立虎尾科技大學/電機資訊學院/光電工程系光電與材料科技碩士班/碩士(2017年)

摘要

本研究的目的改善大面積有機發光二極體發光均勻度，因透明陽極ITO的阻抗較大及壓降的關係導致有亮度不均勻的現象，所以使用Ni、Au兩種金屬製作平行金屬線當輔助電極將電流均勻導入整個元件，改善發光不均勻的問題。首先製作綠色螢光元件最佳化參數，發光面積為1.5 x 1.5cm2，元件結構為：ITO / NPB / Alq3 /TPBi/ LiF / Al，在20mA/cm2電流密度之下效率為4.63cd/A，在發光亮度為100 cd/m2時，元件驅動電壓為4.8 V。導入發光面積3.4 x 3.4 cm2中元件有發光不均勻的現象，再加入Ni or Au輔助電極(間距為2、4、6mm)，發現元件亮度及效率大幅下降推測是表面平整性造成，所以在蒸鍍完輔助電極後旋塗一層PEDOT:PSS降低表面粗糙度，元件結構為：ITO / Ni or Au /PEDOT:PSS(spin)/ NPB / Alq3 / TPBi / LiF / Al，在20mA/cm2電流密度之下發光亮度為649cd/m2，電流效率為3.25cd/A，以九宮格區域量測最低亮度為54cd/m2，平均亮度為55.8cd/m2，發光均勻度達96.8%，間距6mm、厚度11nm 的Ni輔助電極發光均勻度最高，比無輔助電極的ITO均勻度提升7.4%。

關鍵字

有機發光二極體 ； 大面積 ； 輔助電極 ； 均勻度

並列摘要

The purpose of this research to improve the uniformity of large area organic light-emitting diode, because the transparent anode ITO impedance and voltage drop caused by the phenomenon of uneven brightness, the use of Au,Ni two kinds of metal parallel wire as the auxiliary electrode to the current evenly into the entire component, to improve the problem of uneven light. First, create a simple green fluorescent element optimization parameters, device emitting area 1.5 x 1.5cm2.The device structure: ITO / NPB / Alq3 / TPBi / LiF / Al. At the current density 20mA / cm2, current efficiency 4.63 cd/A, the brightness of 100 cd/m2, the device driving voltage was 4.8 V. In the emitting area of 3.4 x 3.4 cm2, the device is luminescent uneven. And then add Ag or Au or Ni auxiliary electrode (spacing is 2, 4, 6mm) , fund that the component brightness and efficiency of a substantial decline in speculation is caused by surface flatness, so spin coating a layer of PEDOT: PSS after the deposition of auxiliary electrode reduce surface roughness, The device structure : ITO / Ag or Au or Ni / PEDOT:PSS(spin)/ NPB / Alq3 / TPBi / LiF / Al. At the current density 20mA / cm2, the emission luminance of 649cd / m2, the current efficiency of 3.25cd / A, the emission luminance uniformity test, the minimum luminance of 54cd / m2, the average luminance of 55.8cd / m2, the luminous uniformity of 96.8% . The spacing of 6mm, the thickness of 11nm Ni auxiliary electrode luminous uniformity of the highest, than no auxiliary electrode ITO uniformity increased by 7.4%.

並列關鍵字

Organic light-emitting diodes ； Large-area ； Auxiliary electrode ； Uniformity

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