臺灣博碩士論文加值系統

無機太陽能電池儘管效率已達24.7%，多層結構更將近34%，但是矽原料短缺、製程機台昂貴且複雜，成本因此居高不下，對於商業應用實有困難。有機共軛高分子太陽能電池不僅製程簡單、成本低廉，因具備可撓特性，元件可隨著空間作形狀變化；噴墨印刷及刮刀的技術更可以將元件朝向大面積、大尺寸發展，以上優點都使得此第三代太陽能電池在未來的發展上極具潛力與想像空間。
我們以氧化物—碳酸銫 (Cs2CO3) 與三氧化鉬 (MoO3) 分別作為電子與電洞的注入層，並且藉此與ITO及金屬接觸後產生一電偶極 (Dipole) 因而調變陰陽極功函數使元件成反相結構；主動層材料我們採BHJ系統，以P3HT混合PCBM於鄰-二氯苯 (DCB)，利用旋轉塗佈的方法在ITO基板上成膜。
本論文藉由各種條件的調變以得到高效率元件，並且，由於元件的電極單薄 (10nm~20nm)，因此同時具備光穿透的能力。最終我們得到最佳效率近3.7% (銀電極)；而金為電極時效率為2.84%，金屬面照光仍有1.8%，光波長在650nm~850nm穿透率達50%~65%。如此光穿透能力對於未來『多層結構』的製作上是我們獨有的優勢，發展空間也因而有更多的選擇性。

Although the efficiency of inorganic solar cells have been reached 24.7% and even 34% for tandem cells, it is not suitable for commercial application due to its high cost. Much more attention has been put to organic solar cells due to its simple and cost-effective fabrication process. Furthermore, flexible substrates and the potential to scale up to large area make it a promising alternative to silicon-based solar cell.
In our study, cesium carbonate (Cs2CO3) and molybdenum oxide (MoO3) have been used as electron- and hole- transport layers. Besides, they also change work function of ITO and metal electrode by forming a thin dipole layer. A bulk heterojunction BHJ consisting blending of P3HT and PCBM in 1, 2-Dichlorobenzene spin-coated on ITO-coated glass is used as our active layer. For device with silver as cathode, the best PCE we studied is almost 3.7%. For device with gold as cathode, we have 2.8% for glass-illumination and 1.8% for metal-illumination. Further, Transmittance is up to 50%~65% within the spectrum from 650nm to 850nm. It would be our specific predominance and make us have more thoughts and choices to fulfill highly-efficient tandem cells.

摘要..............................................................................................................................Ⅰ
致謝..............................................................................................................................Ⅲ
目錄..............................................................................................................................Ⅵ

第一章 序論..................................................................................................................1

1.1研究背景…..............................................................................................1
1.1.1 太陽能電池產業發展…............................................................1
1.1.2 有機太陽能電池........................................................................2

1.2反相結構太陽能元件文獻回顧..................................................................4
1.3研究動機......................................................................................................8
1.3.1 有機高分子太陽能電池的優點................................................8
1.3.2 P3HT與PCBM混合有機高分子太陽能電池.........................9
1.3.3 為何發展反相太陽能電池........................................................9

1.4論文架構....................................................................................................10

第二章 實驗原理........................................................................................................11

2.1太陽能元件簡介........................................................................................11
2.1.1 基本原理..................................................................................11
2.1.2 操作原理..................................................................................13
2.1.3 基本參數介紹..........................................................................17

2.2共軛高分子材料特性................................................................................18
2.3研究結構與理論........................................................................................20

第三章 實驗流程........................................................................................................23

3.1 ITO基板蝕刻與圖樣化.............................................................................23
3.1.1 ITO清洗...................................................................................23
3.1.2 乾式光阻黏貼..........................................................................23
3.1.3 UV紫外光曝光........................................................................24
3.1.4 顯影..........................................................................................24
3.1.5 蝕刻..........................................................................................25

3.2使用儀器、器具與材料............................................................................25
3.2.1 儀器..........................................................................................25
3.2.2 器具..........................................................................................26
3.2.3 溶劑..........................................................................................26
3.2.4 材料..........................................................................................26

3.3 圖案化ITO前置清洗..............................................................................27
3.4 Inverted Cell氧化物及高分子成膜..........................................................27
3.4.1 Cs2CO3 碳酸銫旋轉塗佈........................................................27
3.4.2 Cs2CO3 碳酸銫蒸鍍................................................................28
3.4.3 P3HT/PCBM主動區域............................................................29
3.4.4 MoO3三氧化鉬蒸鍍................................................................30

3.5 Normal Cell各層高分子之成膜................................................................30
3.5.1 ITO基板親水性.......................................................................31
3.5.2 PEDOT：PSS電洞傳輸層......................................................31
3.5.3 P3HT/PCBM主動區域............................................................31

3.6陰極電極蒸鍍............................................................................................32
3.7封裝............................................................................................................33
3.8量測............................................................................................................34

第四章 實驗結果討論................................................................................................35

4.1氧化物的特性與應用................................................................................35
4.2碳酸銫的溶液製程 (Solution process).................................................... 38
4.2.1 碳酸銫存在與否的影響..........................................................38
4.2.2 碳酸銫旋轉塗佈後加熱除水之時間長短的影響..................39
4.2.3 碳酸銫水溶液各濃度下調變轉速測試..................................40
4.2.4 固定轉速下碳酸銫各濃度的元件特性比較..........................43
4.2.5 調變主動層轉速之元件比較..................................................45
4.2.6 金屬電極『金』的蒸鍍速率對元件的影響............................46
4.2.7 結論..........................................................................................47

4.3碳酸銫的蒸鍍製程 (Evaporation process)
—半透明元件................................48
4.3.1 碳酸銫存在與否的影響..........................................................48
4.3.2 各碳酸銫厚度下調變主動層轉速..........................................51
4.3.3 退火溫度對元件的影響..........................................................53
4.3.4 金屬電極的厚度與元件特性關係..........................................53
4.3.5 主動層溶液攪拌時同時加熱的重要......................................54
4.3.6 三氧化鉬的加入......................................................................55
4.3.7 加入三氧化鉬後金屬電極厚度的影響..................................58
4.3.8 最佳化之元件..........................................................................59
4.3.9 薄電極之上下照光..................................................................61
4.3.10 階梯狀曲線的現象..................................................................64

4.4碳酸銫的蒸鍍製程 (Evaporation process)
—高效率且透光元件....................67
4.4.1 三氧化鉬的加入......................................................................67
4.4.2 金屬電極銀的氧化..................................................................68
4.4.3 主動層厚度的效應..................................................................70
4.4.4 調變金屬電極厚度的元件效益..............................................71
4.4.5 最佳化之元件..........................................................................72
4.4.6 薄電極之上下照光..................................................................75
4.4.7 結論..........................................................................................78

4.5光的吸收與穿透........................................................................................78
4.5.1 調變電極厚度之元件穿透與吸收..........................................78
4.5.2 碳酸銫對光穿透的影響..........................................................82
4.5.3 三氧化鉬對光穿透的影響......................................................84
4.5.4 金厚度120nm與200nm的各穿透率比較............................88
4.5.5 元件IPCE與穿透率................................................................93
4.5.6 結論..........................................................................................93

第五章 總結................................................................................................................95
參考文獻......................................................................................................................96

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