本論文之主要研究係利用全透明式電極設計方式及製作多層抗反射層(anti-reflection coating, ARC)於三五族多接面太陽能電池(InGaP/InGaAs/Ge triple-junction solar cell)上之特性研究。由於傳統式金屬電極在太陽能電池元件上會有遮光效應(shadow effect)影響，故採用全透明式電極設計使遮光效應降至最低，進而讓更多太陽光入射並引入元件內部而增強元件之光伏效應。此外，利用(NH4)2Sx鹼性溶液處理太陽能電池之窗層(n-type AlInP)，以改善薄金屬(thin AuGeNi/Au, 5nm/2nm)與銦鍚氧化物(ITO)之間歐姆接觸(ohmic contact)之特性，進而降低元件之串聯電阻值，提高載子萃取能力。而由傳輸線模型(TLM)製作結果顯示，薄金屬與銦鍚氧化物間特徵接觸電阻值(specific contact resistance)經過硫化處理後可降至6.83×10-6Ωcm2。另一方面，吾人利用固定射頻磁控濺鍍系統(sputter system)基座，使濺鍍槍以斜向方式成長低折射率之抗反射膜，使其增強抗反射層之抗反射效果並減少入射太陽光反射之損耗，進而提高太陽能電池元件之轉換效率至30.3%。
本研究之主要目的為探討如何減少入射太陽光之損失，因此本研究採用全透明式電極設計以及改善抗反射層之抗反射特性兩種方式來增強元件之光伏效應特性。由實驗結果得知，應用此兩種方式可將太陽能電池之光電轉換效率提昇至31.92%。

To improve the conversion efficiency of the tandem-type III–V multi-junction solar cell, the transparent electrode designed solar cell and low reflectivity of anti-reflection coating (ARC) on conventional metal electrode solar cell were fabricated. The transparent electrode of indium tin oxide (ITO) material was used to substitute the conventional metal electrode on solar cell for increasing the illuminated area. Moreover, applying the (NH4)2Sx treatment on the AlInP surface before the transition layer deposition, the ohmic contact property of thin AuGeNi/Au and ITO can be improved. According the measurement of TLM fabrication, the specific contact resistance by (NH4)2Sx treatment was 6.83×10-6Ωcm2. Therefore, this method can decrease the resistivity and reduce the loss of the photo-induced carriers. Furthermore, in order to reduce the losses of solar reflection, multi-layer ARC and oblique sputtering by fixing holder of sputter system were used to deposit low reflection of ARC material. The conversion efficiency was 30.3% by this technology fabrication for solar cell device.
In our research, using the transparent electrode to replace metal electrode and oblique sputtering to deposit low reflective index material can effectively reduce the losses of incident solar reflection and promote the conversion efficiency of solar cell device. The 31.92% conversion efficiency of solar cell can be achieved by using the transparent electrode design and anti-reflection coating (ARC) improvement method.

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