透明電極對透明有機發光二極體之效應

Influences of Transparent Electrodes on Characteristics of Transparent Organic Light-Emitting Diodes

柯婷瑋(Ting-Wei Ko)

指導教授 ： 吳忠幟

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2016年)

https://doi.org/10.6342/NTU201601650

摘要

近年來，有機發光二極體快速發展成一具有潛力的平面顯示與照明技術，其中，有機材料的透明性使得有機發光二極體未來具有更廣泛的應用，例如可使窗戶具備顯示的功能。因此，有許多研究致力於發展透明有機發光二極體。為了滿足高效率、低操作電壓、長壽命的顯示元件特性，我們必須設法了解透明元件的光學特性，來達到最佳的外部出光效率，並維持元件的高穿透度。
在本論文研究的第一部分，我們說明了光學模擬所應用的原理，並透過此模型來預測不同的透明電極之元件結構特性，並就模擬的結果作分析與討論。接著，我們實作出應用透明導電高分子電極的透明有機發光二極體元件，將其實驗結果與模擬相比較，並推測與模擬結果有所出入的原因。
在本論文研究的第二部分，我們將使用導電高分子電極之透明有機發光二極體元件堆疊加上高折射率二氧化鈦薄膜，利用此薄膜使透明元件的微共振腔效應增強，進而提高其總和外部量子效率。並觀察到改變元件結構能調整穿透度頻譜的峰值位置，使元件在未點亮前，因不同結構下呈現不同的顏色變化，使得透明元件更具有特色。

關鍵字

透明電極 ； 有機發光二極體 ； 光學模擬 ； 高折射率薄膜 ； 微共振腔

並列摘要

Organic light-emitting devices (OLEDs) have been demonstrated as an important display and lighting technology. Among various advantages, transparency of organic materials can further extend applications of OLEDs, for instance, making windows as displays. Therefore, many researchers have been devoted to developing transparent OLEDs. It is necessary to understand the optics in transparent devices so that we can optimize the external quantum efficiency and maintain high transparency to attain high efficiency, low operating voltage and long lifetime.
In the first part of this thesis study, we predict the characteristics of transparent OLED structures using different transparent electrodes by optical simulation data. Then we conducted experiments on OLEDs which adopted the PEDOT:PSS transparent electrode. By comparing the experiments and simulation data, we analyze the reason that result in the difference between the simulation and the experiment data.
In the second part of this thesis study, we apply the high-refractive-index TiO2 thin film to the OLEDs with PEDOT:PSS electrodes. With enhancing the microcavity of transparent OLEDs, the high-index thin film can improve the total external quantum efficiency. In addition, we can adjust the structure to shift the peak of transmittance spectra, resulting in different colors of transparent OLEDs which may find some interesting applications.

並列關鍵字

transparent electrodes ； Organic light-emitting devices (OLEDs) ； optical simulation ； high refractive index thin film ； microcavity

參考文獻

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