Enhanced Brightness and Efficientcy in Polymer Light-Emitting Diodes (PLED) Using Alq(subscript 3) Electron-Transporting Layer

使用Alq(subscript 3)電子傳輸層於高分子發光二極體之增強發光亮度與效率

黃建榮(C. J. Huang) ； 李靜純(C. C. Lee) ； 邱品翔(P. H. Chiu)

《真空科技》 17卷1期 (2004/07) Pp. 69-74

https://doi.org/10.29808/JVSROC.200407.0011

摘要

本文係研究將電子傳輸層（Alq(subscript 3)）材料插入介於陰極（Al）與發光層（PF）之間有助於改善高分子發光二極體的電致發光效率。當切入電壓於2.5伏特時有插入Alq(subscript 3)層的元件電致發光效能比起未使用Alq(subscript 3)層元件顯現大幅改善，當插入Alq(subscript 3)的厚度為10 nm時會導致高分子發光二極體（PLED）載子傳輸有個平順的能障高度，提升電子注入於陰極，而且Alq(subscript 3)的表面平均粗糙度有最小的數值約為0.790 nm。另外，插入Alq(subscript 3)層的發光之驅動電壓為5伏特有3.51 cd/㎡的亮度，而最大的發光亮度為361.8 cd/㎡，元件發光面積為1.5×0.3 cm(superscript 2)。元件的色度放射出黃綠光為536 nm，而CIE色譜圖為（0.39, 0.57）。

關鍵字

電致發光 ； 高分子發光二極體

並列摘要

We report that an electron-transporting layer of Alq(subscript 3) is interposed between a cathode of Al and an emissive layer of Polyfluorene (PF) which can significantly improve electroluminescence efficiency in a polymer light emitting diode (PLED). The difference of the turn-on voltage is about 2.5 V for with and without insertion of a thin Alq(subscript 3) layer, which greatly improves the EL performance compared with the devices without an Alq(subscript 3) layer. The thickness of Alq(subscript 3) is 10nm, which is resulted in the smooth energy barrier height on PLED and promoted electron injection in the cathode section. The average surface roughness of Alq(subscript 3) under thickness 10 nm is the smallest about 0.790 nm. Besides, the turn-on voltage of luminescence with Alq(subscript 3) defined by 3.51 cd/㎡ is 5 V. A maximum luminescence is obtained at 361.8 cd/㎡. The emission area is 1.5×0.3 cm(superscript 2). The devices show the yellow-green light emission with a peak at about 536 nm. The color coordinate in CIE chromaticity is (0.39, 0.57).

並列關鍵字

electroluminescence (EL) ； polymer light emitting diode (PLED)