臺灣博碩士論文加值系統

Alq3 這樣的小分子材料過去被廣泛的應用在OLED 中，被定位
成不適用於有機太陽能電池的發光材料，如今我們將著重於其三重態
激子擁有生命期明顯比單重態激子長的特性，若我們能把此特性應用
在太陽能電池中則可望提升其光電轉換效率而令其有了應用在太陽
能電池的可能性。在本文中，吾人用共蒸鍍鎂與Alq3 的方法發現Alq3
將形成一種新的有機金屬，其單重態激子由系統內部轉移到
(Intersystem crossing process)三重態的比例會大幅提升，而這些結果均
可由光激螢光光譜(PL)，時間鑑別光激螢光光譜量測系統(TRPL)，吸
收頻譜(Optical absorption)，分子模擬(molecular simulation)等等的實
驗中獲得證實。

Tris-(8-hydrozyquinoline)aluminum (Alq3), is one of the most
frequently used low-molecular weight materials for organic light-emitting
devices(OLEDs), and is a so called fluorescence emitter, but it’s triplet
exciton are also expected to play an implortant role in the organic
photovoltaic devices. Because of the spin statistic of the exciton, the
lifetime of these triplet exciton are significanty longer than that of the
singlet exciton. If the long lifetime of these triplet exciton can be used, it
will result in long exciton diffusion lenth which is good for organic solar
cells devices. In my research, I use the Mg-modified Alq3
hetrohomogeneous thin film to be n type material which behavior an
enhanced singlet to triplet exciton exchange, and we found it can promote
electron injection in organic electronic devices, provide proper energy
step for the p-n junction, and enhance the conductivety between the
interface of Mg-modified Alq3 and Ag layers.

目錄
摘要............................................................................................................. I
Abstract ......................................................................................................II
致謝...........................................................................................................III
目錄.......................................................................................................... IV
圖目錄...................................................................................................... VI
表目錄...................................................................................................... IX
表目錄...................................................................................................... IX
第一章 簡介...............................................................................................1
第二章 操作原理與材料特性..................................................................3
2.1 太陽能電池操作原理與轉換效率...............................................3
2.2 有機半導體 (Organic Semiconductor)......................................15
2.3 Tris(8-Hydroxyquinolato) Aluminum (Alq3)之材料特性介紹
...........................................................................................................23
第三章 實驗方法....................................................................................28
3.1 製程儀器.....................................................................................28
3.2 量測儀器....................................................................................32
第四章 結果與討論................................................................................39
4.1 研究目的....................................................................................39
4.2 將Alq3 參雜鎂之後對元件之影響............................................41
4.3 電性量測.....................................................................................43
4.4 比較ZnPC 與Alq3 層之光電流貢獻........................................45
4.5 參雜鎂對Alq3 內部電荷分布之影響........................................48
4.6 三重態激子來源.........................................................................50
4.7 光激螢光光譜量測之分析.........................................................52
4.8 時間鑑別光激螢光光譜之分析.................................................60
4.9 實驗吸收頻譜與模擬吸收頻譜之比較....................................64
第五章 結論.............................................................................................66
參考文獻...................................................................................................67



圖目錄
圖2-1 太陽能電池原理.............................................................................3
圖2-2 光電流損失機制流程圖.................................................................7
圖2-3 圓格線表照光下之I-V 曲線；方格線表未照光下的I-V 曲線10
圖2-4 太陽能電池等效電路圖...............................................................11
圖2-5 有機半導體之能階圖...................................................................17
圖2-6 NPB and Alq3................................................................................17
圖2-7 ZnPc 之吸收光譜.......................................................................19
圖2-8 ZnPc 之化學結構式...................................................................19
圖2-9 元件能帶圖..................................................................................22
圖2-10 延遲電子螢光光譜示意圖(delayed electroluminescence) .......26
圖2-11 變溫時間延遲電子螢光光譜(temperature dependent EL).......26
圖2-12 磷光生命週期量測..................................................................27
圖3-1 蒸鍍機...........................................................................................28
圖3-2 手套箱...........................................................................................29
圖3-3 點膠機..........................................................................................30
圖3-4 UV 膠............................................................................................30
圖3-5 UV 燈............................................................................................31
圖3-6 光激螢光原理示意圖..................................................................33
圖3-7 光激螢光光譜量測系統架設示意圖..........................................34
圖3-8 時間鑑別光激螢光光譜量測系統示意圖..................................36
圖3-9 太陽光源模擬系統......................................................................37
圖3-10 電源供應器.................................................................................37
圖3-11 UV/VIS/NIR Spectrophotometer ................................................38
圖4-1 兩層結構之有機太陽能電池能階圖...........................................42
圖4-2 不同參雜鎂之比例之有機太陽能電池電流密度......................44
圖4-3(a)各層之吸收頻譜........................................................................46
圖4-3(b)不同參雜鎂比例之元件的EQE 量測.....................................47
圖4-4 Alq3 之能階圖譜.......................................................................51
圖4-5(a)燈光源螢光頻譜........................................................................52
圖4-5(b)其峰值位置隨不同激發波長之變化.......................................53
圖4-6(a) 396nm 雷射系統系統所量測之光激螢光光譜.....................55
圖4-6(b) 325nm 雷射所量測之螢光光譜.............................................55
圖4-6(c) 266nm 雷射系統所量測之光激螢光光譜.............................56
圖4-6(d) 266nm 雷射對Alq3:Mg = 1:0 之樣品的變溫螢光光譜測量57
圖4-6(e) 266nm 雷射對Alq3:Mg = 1:1 之樣品的變溫螢光光譜測量58
圖4-6(f) 以溫度與激發光源波長為變因之螢光光譜模型..................58
圖4-7(a)(b)螢(磷)光之生命期量測........................................................61
圖4-7(c) 396nm 脈衝雷射系統所測之螢光光譜原始強度頻譜.........63
圖4-8(a) 吸收光譜實驗值......................................................................65
圖4-8(b) 吸收頻譜模擬.........................................................................65



表目錄
表2-1 ZnPc 之材料特性整理...............................................................20
表2-2(a) Alq3 之基本物理特性...............................................................24
表2-2(b) 元素功函數.............................................................................25
表4-1 表格整理.......................................................................................44
表4-2 表格整理......................................................................................61

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