偏振OLED之研究

A Research for Polarized Organic Light Emitting Diode

郭文政(Wen-cheng Kuo)

指導教授 ： 李正中 ； 張興華

國立中央大學/理學院/光電科學研究所/碩士(2007年)

摘要

近幾年高分子偏振性的有機電激發光元件被製作出來，因其能夠減少偏振片的數目、簡化製造程序及降低成本，所以漸受到重視。但在目前OLEDs市場上，還是以小分子材料製成的成品居多。可是以小分子為偏振發光薄膜的研究較少見於文獻中。因此本論文就以小分子材料的偏振有機電激發光元件為研究的主軸。我們首次整合了高分子配向膜的技術，並結合斜向熱蒸鍍小分子的方法成功地製作出偏振有機電激發光的元件。

藉由斜向蒸鍍的方法，小分子材料能形成規則性的薄膜。我們首先利用斜向蒸鍍的技術蒸鍍小分子Alq3薄膜，並成功地做出具有偏振度為3的ITO/m-MTDATA/α-NPD/Alq3/LiF/Al偏振性的有機電激發光元件。

為了改進元件的偏振度，我們整合了高分子配向膜的技術來增加斜向熱蒸鍍薄膜排列的規則性。我們以摩擦配向的高分子PVK為電洞傳輸層，再以斜向熱蒸鍍的方式將DPBVi鍍上以形成異質接面的結構。最後成功地做出偏振元件ITO/PEDOT/PVK/DPVBi/Alq3/
LiF/Al。其中元件偏振度提升到24，這種元件偏振度在LCD平面顯示器市場上已具實用性。

關鍵字

偏振 ； OLED

並列摘要

Recently, polarized polymer OLEDs is of practical interest because they may facilitate the fabrication of liquid crystal displays without polarizer, which will lead to simplification of display manufacture and reduction of cost. However, in OLEDs market, small molecule materials are used largely than polymer materials in manufacturing OLEDs now. But polarized OLEDs using small molecule ordered film are rarely found in the literature. In this thesis, polarized OLEDs using small molecule materials are studied.
By utilizing oblique evaporation method, small molecule materials are aligned to form ordered structure. Incorporating obliquely evaporated Alq3 film in device ITO/m-MTDATA/α-NP/Alq3/LiF/Al, polarized OLEDs are fabricated successfully with polarization ratio 3.
In order to improve the polarization ratio of the device, rubbing alignment technique used in polymer polarized OLEDs are integrated to enhance orientation of obliquely evaporated film. We use PVK as an hole transport alignment layer by mechanical rubbing. After that, blue DPVBi emitting materials are deposited obliquely on it to form heterojunction structure. Polarized device, ITO/PEDOT/PVK/DPVBi/Alq3/LiF/Al, are fabricated successfully. EL polarization ratio is raised up to 24 to be available for LCD flat display application.

並列關鍵字

polarized OLED

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