銅銦鎵硒 (Cu(In,Ga)Se2, CIGS) 是太陽能電池產業最具潛力的材料之一。本論文著力於單一四元靶材濺鍍製程的開發，此簡單的製程若能大面積化，在未來將有極高的工業價值。

這份工作裡，我們採用升溫鍍膜的方式，以單一四元靶材、一階段濺鍍且不需額外硒供應，製作出 CIGS 太陽能電池吸收層，並完成完整元件。我們分別探討富銅與缺銅兩種不同成分靶材所製作出來的 CIGS 薄膜的電性、結構特性與元件特性。我們發現在銅缺乏的靶材中，薄膜的晶界鈍化十分重要，因此更進一步研究鈉元素摻雜在此製程裡對晶界鈍化以及元件效率的幫助。

在富銅靶材的研究中，我們得到了 6\% 的轉換效率，過高的載子濃度與銅含量可能限制了元件的效率。於缺銅靶材的研究中，我們藉由控制鈉的摻雜，將轉換效率由最初的 0.2%，提升至超過 7.5%。

Cu(In , Ga ) Se2 (CIGS)-based solar cell is one of the most promising candidates for future photo-voltaic application. In this thesis, we developed a one-step sputtering process from a single quaternary target. This straightforward process might be suitable for large-area application in industry.

In this work, CIGS thin films were fabricated by sputtering from a single target at elevated temperature without additional selenium supply. Both film properties and device properties were investigated. Two targets with different composition were studied, namely, one copper-poor target and one copper-rich target. In the study concerning copper-poor target, we found that grain boundary passivation was quite critical. Hence, additional efforts were put into sodium incorporation.

For the copper-rich target, the efficiency of 6\% was achieved. However, high carrier concentration and high copper concentration might limit the device performance. For the copper-poor target, the conversion efficiency was increased from 0.2\% to over 7.5\% by controlling sodium composition.

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