臺灣博碩士論文加值系統

近年來有機發光二極體（OLED）已經逐漸進入顯示市場甚至是嶄新的領域，因此發展一套有助於設計有機材料裝置的模擬軟體是很重要的。之前，我們發展了將高斯等效能態密度和普爾 - 弗蘭克爾（Poole-Frenkel）遷移率模型帶到一維的泊松及漂移擴散方程解（Poisson and drift-diffusion solver）來模擬有機材料。

在本篇論文中，我們研究了考慮材料的吸收頻譜來設定等效能態密度分佈的方法。結果顯示這是一個更恰當的方法模擬建立有機材料的等效能態密度。

此外，為了解決低濃度下的參雜的影響而發展二維隨機參雜模型。我們也用二維有限元素法去計算激子的分佈和內部量子效率。結果指出與實驗數據符合。

Organic light emitting diodes (OLEDs) have been gradually entering the display markets and even special light area in recent years.
Therefore, it is important to develop a useful simulation tool assisting in the device design of the organic materials.
In the past, 1D Poisson and drift-diffusion solver have been developed by considering Gaussian-shaped density of state and Poole-Frenkel model to simulate organic materials.

In this thesis, we study the method about setting up the distribution of density of state by considering the absorption spectrum of the material.
The result shows that is a more appropriate method in modeling the density of state in organic materials.

Moreover, 2D random dopant model is hence developed to treat the effect of random doping distribution in low doping conditions.
We further calculate the 2D exciton distribution and the internal quantum efficiency (IQE) by 2D finite element method.
The results show that it is consistent with experimental data.

口試委員會審定書. . . . . . . . . . . . . . . . . . . . . . . . . i
誌謝. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
中文摘要. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
英文摘要. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
目錄. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
圖目錄. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
表目錄. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Introduction to OLED Device . . . . . . . . . . . . . . 3
1.3 Density of State with Absorption Spectrum . . . . . . 6
1.4 Poole-Frenkel Mobility Model . . . . . . . . . . . . . . 7
1.5 Effect of Doping . . . . . . . . . . . . . . . . . . . . . . 10
2 Simulation Method . . . . . . . . . . . . . . . . . . . . . . . 13
2.1 Simulation Flow Chart . . . . . . . . . . . . . . . . . . 13
2.2 Drift-Diffusion Charge Control . . . . . . . . . . . . . . 14
2.3 Random Dopant Model . . . . . . . . . . . . . . . . . . 18
2.4 Efficiency Calculation . . . . . . . . . . . . . . . . . . 20
3 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.1 Simulated Results by Considering Absorption Spectrum 23
3.1.1 EOD of DPPS . . . . . . . . . . . . . . . . . . . 23
3.1.2 EOD of ID-8 . . . . . . . . . . . . . . . . . . . 27
3.1.3 HOD of ID-8 . . . . . . . . . . . . . . . . . . . 31
3.2 Simulated Results of 2D Random Dopant Model . . . . 33
3.2.1 J-V characteristic . . . . . . . . . . . . . . . . . 36
3.2.2 Excitons and Efficiency . . . . . . . . . . . . . . 41
4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

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