高三重態能隙有機半導體材料之特性與元件應用

Characterization and Device Applications of High-Triplet-Energy Organic Semiconductors

黃師軒(Shih-Hsuan Huang)

指導教授 ： 吳忠幟

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.03394

摘要

有機發光二極體(OLED)近年來在平面顯示器與白光照明應用上逐漸成熟。與目前主流顯示技術液晶顯示器(LCD)相比，OLED具有輕薄、高對比度、高鮮明度色彩、可視角度大(可達170°)、不需要背光源(自發光)，高發光效率、反應速度快(~1μs)、可彎曲等特性，可製成大尺寸以及可撓式面板。目前從小尺寸顯示器如手機與PDA顯示面板已經逐漸由OLED所取代，隨著技術不斷研發，OLED的前景無可限量。
在OLED元件開發上，目前已由能量轉換效率較高的磷光元件研究取代螢光元件，而新穎的材料更是不斷的被設計與研發以求得更好的元件效率。本論文主要研究的材料為以具有給電子效果的咔唑為主體的分子搭配上的具有拉電子效果的亞碸官能基，嘗試製作出同時具有雙載子傳輸特性的分子。於本研究中將兩種化合物cbz-di-SO2與SO2mCP進行物理性質的量測以及運用到OLED元件中進行測試，藉由不同的電子傳輸層以及電洞傳輸層材料搭配找出兩種材料的特性比較，並利用電子傳輸層的階梯式LUMO能階結構改良元件以得到不錯的元件效率。

關鍵字

亞碸咔唑 ； 高三重態 ； 磷光 ； 有機發光二極體 ； 雙極性

並列摘要

Organic Light Emitting Device (OLED) technology is emerging as a promising technology for displays and lighting. OLEDs possess key performance features including vibrant color, high contrast ratios, full-motion video, and wide viewing angles. In two different light-emitting mechanisms, phosphorescent OLEDs can have up to four times higher efficiency than fluorescent OLEDs, because the incorporation of heavy metal-containing complexes into appropriate host materials allows the harvesting of both singlet and triplet excitons and make it possible to achieve nearly 100% internal quantum efficiency. The development of PHOLED therefore has attracted a great deal of attention, and the adoption of bipolar host materials is becoming an important method to improve device performances.
Two novel materials were under studied in this research. Materials combining carbazole-based main structures, which are considered to give hole-transport ability, and sulfone group, which is expected to be electron-transport part of the molecule, is believed to give bipolar ability, and the large triplet energy (> 2.8 eV) is suitable for PHOLED host materials. Both two materials have high PLQY about 80% when doping with Ir(ppy)3 and FIrpic, but the devices can’t reach equal performances. The properties of these two materials in devices were studied by applying different materials into the hole-transport layer and the electron-transport layer. Having more sulfone groups, cbz-di-SO2 shows stronger electron-transport property than SO2mCP.

並列關鍵字

Sulfone ； carbazole ； high-treplet ； phosphorescence ； OLED ； bipolar

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