臺灣博碩士論文加值系統

本論文利用雷射干涉微影技術製作奈米金屬網電極於InGaP/InGaAs/Ge三接面太陽能電池。相較於傳統指叉狀電極，利用雷射干涉微影技術製作金屬網可以有效降低金屬電極間距使串聯電阻變小且可以有效降低金屬遮蔽率，最終提高InGaP/InGaAs/Ge三接面太陽能電池之轉換效率。利用奈米金屬網取代傳統指叉狀電極於InGaP/InGaAs/Ge三接面太陽能電池，當奈米金屬網之金屬線間距為100 μm時，其元件之短路電流密度由17.3 mA/cm2提升至18.9 mA/cm2，轉換效率由30.84%提升至34.87%，而金屬遮蔽率由7.50%下降至0.66%，串聯電阻由9.1 Ω-cm2降低至7.9 Ω-cm2。為進一步提升InGaP/InGaAs/Ge三接面太陽能電池之轉換效率並改善傳統的抗反射膜利用單層或雙層膜堆疊設計以達到特定波長之反射率降低為零，但在其它波段之反射率卻會提升至10%以上之缺點。本論文利用雷射干涉微影技術藉由犧牲層製作二維陣列，並搭配電子束斜向蒸鍍技術成長二氧化鈦(TiO2)奈米結構之抗反射層，此奈米結構具有粗化及漸變折射率之效果，可以改善試片窗口層與空氣因折射率差而導致過多光反射，藉以取代傳統抗反射膜。利用二氧化鈦奈米結構取代傳統抗反射膜作為InGaP/InGaAs/Ge三接面太陽能電池之抗反射層，當二氧化鈦奈米結構週期為1 μm時，其結構之平均反射率約為1.095%，等效折射率約為1.79。此外，將二氧化鈦奈米結構搭配奈米金屬網電極製作於InGaP/InGaAs/Ge三接面太陽能電池，元件之短路電流密度由18.90 mA/cm2及提升至19.51 mA/cm2，轉換效率由34.87%提升至36.02%。

In this study, the laser interference photolithography technique and oblique evaporation method by electron beam evaporation system were used to fabricate the nanomesh electrode and the TiO2 nanostructured as the antireflection coating on the InGaP/InGaAs/Ge compound triple-junction solar cell. By using the nanomesh electrode with the metal line interval of 100 μm, the conversion efficiency of the InGaP/InGaAs/Ge triple-junction solar cells improved to 34.87% compared with 30.84% of the solar cells with the conventional bus-bar metal electrode. To further improve the conversion efficiency of the solar cells and improve the drawback of the conventional antireflection coating, the TiO2 nanostructured substituted as the antireflection coating. By using the TiO2 nanostructured with the period of 1 μm, the average reflectivity and the effective refractive index were 1.095% and 1.79, respectively. The conversion efficiency of the InGaP/InGaAs/Ge triple-junction solar cells with TiO2 nanostructured was improved to 36.02% compared with 34.87% of the conventional antireflection coating.

摘要 I
Abstract III
致謝 VIII
目錄 X
表目錄 XIII
圖目錄 XIV
第一章 序論 1
1.1 前言 1
1.2 研究動機 2
1.3 論文架構 3
參考文獻 6
第二章 實驗原理介紹 9
2.1 太陽能電池工作原理 9
2.1.1 光電基本轉換原理 9
2.1.2 太陽能電池電流電壓特性 9
2.1.3 填充因子 11
2.1.4 太陽能光譜 11
2.1.5 轉換效率 12
2.2 雷射干涉微影系統 13
2.3 電子束斜向蒸鍍技術 14
2.4 抗反射光學原理 15
2.4.1 單層抗反射層 16
2.4.2 雙層抗反射層 16
2.4.3 漸變折射率抗反射層 17
參考文獻 24
第三章 元件製作與量測儀器 26
3.1 試片結構 26
3.2 元件製作流程 26
3.2.1 背部電極 26
3.2.2 硫化表面處理 27
3.2.3 定義頂部網狀電極 27
3.2.4 選擇性蝕刻 30
3.2.5 定義抗反射層圖形 31
3.3 製程及量測機台介紹 34
3.3.1 磁控式濺鍍系統 34
3.3.2 電子束蒸鍍系統 34
3.3.3 轉換效率量測系統 35
3.3.4 UV-VIS-NIR光譜分析儀 36
參考文獻 45
第四章 實驗結果與討論 46
4.1 奈米金屬網 46
4.1.1 金屬遮蔽率及串聯電阻 46
4.1.2 不同奈米金屬網間距於元件之轉換效率與分析 47
4.1.3 不同金屬線間距於元件之未照光電流電壓曲線與分析 49
4.2 二氧化鈦奈米抗反射結構作為抗反射層 49
4.2.1 不同週期二氧化鈦奈米結構之反射率量測 50
4.2.2 不同週期二氧化鈦奈米結構之等效折射率量測 51
4.3 奈米金屬網電極搭配二氧化鈦奈米抗反射層 52
參考文獻 62
第五章 結論 64

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