本論文主要之研究目的為利用光電化學氧化法針對太陽電池窗層(AlGaAs)表面進行護佈處理，此護佈方式之優點為採用自身氧化法來降低窗層與氧化層間之表面態密度以減少載子表面複合機率，並修補元件漏電路徑進而增加太陽電池轉換效率。
本研究針對砷化鎵太陽能電池(GaAs single-junction solar cell)之窗層表面處理前後，元件轉換效率、電流-電壓特性曲線及表面態密度進行探討。藉由光電化學氧化法成長氧化層方式其表面之懸浮鍵將會與氧形成鍵結，進而減少表面態密度及降低表面復合速率，使元件漏電流降低，整體光電流提昇。另一方面，將藉由電子束蒸鍍系統成長雙層抗反射層(double anti-reflection coating)以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。應用光電化學氧化法可將砷化鎵太陽能電池之光電轉換效率提升至15.7 %。

The purpose of this research is to investigate the passivation mechanism of the window layer (AlGaAs) of GaAs solar cell by using photoelectrochemical oxidation method (PEC). The advantage of this passivation method is using its self-oxidation material to reduce the energy loss from the surface states on the window layer.
The conversion efficiency of the GaAs solar cell with and without photoelectrochemical oxide treatment would be investigated. The conversion efficiency can be improved due to the reduction of surface state densities. Furthermore, in order to reduce the losses from the solar reflection, double anti-reflection coating was fabricated by electron-beam deposition system. In our research, the conversion efficiency was improved to 15.7% by using the photoelectrochemical oxidation method.

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