螢磷混合式白色有機發光二極體P-i-N摻雜結構之研究

The Study of P-i-N Doping Structures in Hybrid White Organic Light-Emitting Diodes

曹文豪(Wen-hao Tsao)

指導教授 ： 莊賦祥

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2014年)

摘要

本論文研究以P-i-N型態的摻雜方式應用於白色螢磷混合式有機發光二極體之中，論文以P型摻雜對於元件的提升與影響為主要比較之重點。本文開頭採用Hole-only元件與Electron-only元件探討不同摻雜材料(MoO3、Liq)之摻雜注入對於OLED元件之提升為主要研究，採用共蒸鍍方式進行摻雜製作，在相同結構以及相同厚度下進行Hole-only元件與Electron-only元件的特性量測，比較兩種材料的不同摻雜濃度，以及其摻雜後對元件的I-V提升變化之效益，而後沿用最佳化的摻雜結果，進行有機發光二極體之製備。接著使用高耐熱之雙極性螢光主發光體UBH-15搭配藍色螢光摻雜客體EB-502作為藍色發光層，以及雙極性之磷光主發光體EPH-31搭配黃色磷光摻雜客體EPY01做為黃色發光層來製作白色螢磷混合式雙發光層有機發光二極體，並且將Liq於ETL層作為N型摻雜，優先探討N-type摻雜對於OLED元件的效果提升。接著調整其黃色磷光發光層之最佳厚度，增加元件中載子進入複合區的平衡狀態，藉此提高元件之發光效率，能夠於磷光發光層濃度為3%時，得到20 mA/cm2下達到18 cd/A之發光效率，且發光亮度達到3600 cd/m2，以此結構元件作為本質元件，加入P型摻雜材料MoO3，增加OLED元件中的電洞注入效果，在20 mA/cm2下，可使得操作電壓由9.4V降低至8.9V，且發光亮度由3600 cd/m2達到3720 cd/m2，發光效率由18 cd/A達到18.6 cd/A，並且討論p-i-n型摻雜對於元件的提升情形及分析，而後使用紅色磷光摻雜材料Hex-Ir(phq)3進行p-i-n元件製備，並調整濃度於3%時獲得最佳元件特性，CIE座標為(0.38,0.39)，形成一暖白光元件，並在最後章節討論P型摻雜區域的增加情況，能夠更將操作電壓在20 mA/cm2下由8.9V降低至7.9V，更進一步的增加了電流注入量。

關鍵字

p-i-n摻雜 ； 白光有機發光二極體 ； 螢磷混合式 ； 雙發光層 ； hole-only元件 ； P-type摻雜

並列摘要

In this thesis, the study of P-i-N type dopants to white hybrid fluorescent and phosphorescent OLED, P-type doping of the thesis is focused on enhancing devices. First, Hole-only devices and Electron-only devices compare different doping materials(MoO3、Liq) for enhancing the OLED devices is the main research. Be produced in the same structure and the same thickness. Compare with different doping concentrations and the I-V promotion for OLED devices. Optimize the use of the Hole-only devices and Electron-only devices for fabrication of organic light-emitting diodes. Then use the high heat host of bipolar fluorescent material UBH-15 with blue fluorescent dopant material EB-502 as a blue emitting layer, and bipolar phosphorescent host material EPH-31 with yellow phosphorescent dopant material EPY-01 as a yellow emitting layer to produce white hybrid fluorescent and phosphorescent OLED. And joined Liq in ETL as N-type doping, discussion the effect of N-type dopants to OLED devices for improvement. Then adjust the optimum thickness of the phosphorescent yellow emitting layer, and increase balance of the carrier recombination. When EPH-31:EPY-01 concentration of 3%, can have more electron-hole pairs combined, at 20 mA/cm2 achieve the luminous efficiency of up to 18 cd/A, and the luminous of up to 3600 cd/m2. The N-type device structure as a basic device, and added the P-type dopant material MoO3 to increase the hole injection in effect of the N-type hybrid OLED devices. And discuss the pin-type doping devices for enhancing the situation and analysis at 20 mA/cm2 achieve the luminous efficiency of up to 18.6 cd/A, and the luminous of up to 3720 cd/m2. Then a red phosphorescent dopant material Hex-Ir(phq)3 fabricated for pin devices, and adjust the optimum concentration of 3% at CIE coordinates (0.38,0.39) to form a warm white light OLEDs. Discussed in the last section of the P-type doped region is increased, At the 20 mA/cm2, the operating voltage can be reduced from 8.9V to 7.9V, further increases the amount of current injection.

並列關鍵字

white fluorescent and phosphorescent OLED ； p-i-n dopant ； hole-only device ； hybrid ； P-type dopant ； double-EML

參考文獻

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