Characterization of Organic Light-Emitting Diodes with Various Aniline-Related Materials as a Hole Injection Layer

以苯胺相關材料作為電洞注入層之有機發光二極體的特性分析

吳哲睿(Jhe-Ruei Wu) ； 邱俊傑(Jiun-Jie Chiu) ； 汪安財(An-Tsai Wang) ； 林谷彥(Ku-Yen Lin) ； 湯秀靜(Shiow-Jing Tang) ； 邱寬城(Kuan-Cheng Chiu)

《先進工程學刊》 9卷4期 (2014/10) Pp. 211-216

摘要

本文探討利用不同的苯胺相關材料作為電洞注入層（Hole injection layer，HIL）對有機發光二極體（Organic light-emitting diode，OLED）性能之影響。HIL是利用旋轉塗佈法將去摻雜後之聚苯胺（Polyaniline, PANI）、聚苯胺／銀奈米複合材（PANI/Ag）、或苯胺寡聚體等三種不同的苯胺材料，塗佈在銦錫氧化物（Indium tinoxide, ITO）玻璃基板上所形成之薄膜；而OLED的基本架構則採用ITO/HIL/NPB/Alq_3/LiF/Al的異質接合形式。由電流密度（Current density, J）-電致發光強度（Electroluminescence intensity, EL）-偏壓（Bias voltage, V）之實驗資料分析，相較於沒有HIL的OLED而言，具有PANI/Ag為HIL的OLED在V =14 V時的EL明顯增強約30倍。隨後，本文再將這些J-V實驗資料，根據不同之電荷載子傳輸機制，作一系列之數值擬合分析。結果顯示若採用Fowler-Nordheim發射模型，具有PANI/Ag或苯胺寡聚體為HIL的OLEDs其J及EL的增強，可歸因於此兩材料做為HIL的加入，導致能量壁障與閾值電壓的下降。

關鍵字

有機發光二極體 ； 電洞注入層 ； 電流密度-電致發光強度-偏壓曲線 ； 聚苯胺 ； 聚苯胺/銀奈米複合材 ； 苯胺寡聚體

並列摘要

Effects from various aniline-related materials used as a hole injection layer (HIL) on the performance of organic light-emitting diode (OLED) were studied. A basic OLED heterostructure of ITO/HIL/NPB/Alq_3/LiF/Al was adopted, and a thin layer formed by dedoped polyaniline (PANI), polyaniline/silver composite (PANI/Ag), or aniline-oligomers was spin-coated on top of indium tin oxide (ITO) glass as the HIL. From the current density (J)-electroluminescence intensity (EL)-bias voltage (V) characteristic curves, an enhancement of EL by a factor of around 30 at V=14 V was obtained for the OLED with aniline-oligomers as the HIL as compared with the one without HIL. Then, the experimental J-V data were numerically analyzed with various charge-carrier transport models. Based on the Fowler-Nordheim emission, the enhancement of J as well as EL was attributed to the reduction of the energy barrier E_B and threshold voltage V_T after the introduction of PANI/Ag composite or aniline-oligomer as the HIL.

並列關鍵字

organic light-emitting diodes ； hole injection layer ； J-EL-V curves ； polyaniline ； polyaniline/silver nanocomposite ； aniline-oligomers