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.

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