銅銦鎵硒薄膜太陽能電池是目前最有最有潛力的第二代太陽能電池之一。其優勢體現在具有直接能隙、優秀的能帶操控性以及輕薄可撓等。目前最高的轉換效率為23.35%，其所用製程為硒化後硫化製程。除了硫化處理，銀合金化也被認爲是一種相當具有潛力的提高效率的方式。但目前大部分對添加銀的研究僅僅停留在硒化以及共蒸鍍的研究，對硒硫化製程的研究知之甚少。
本研究使用濺鍍方式在前驅層中鍍上一層AgGa薄膜，在通過硒化後硫化的方式製作出銀合金且表面硫化的(Ag,Cu)(In,Ga)(Se,S)2吸收層。通過製作高銀含量以及低銀含量之試片探討銀對與硒硫化製程之影響。研究表明，硫化後的試片的Cu,Ag分佈有發生了改變，導致能帶匹配產生改變。以及添加少量銀易使試片產生銅缺相（OVC phase），同樣也會使介面匹配改變。
最後，通過添加10%銀，可以獲得元件效率最高可達15.2%。

CIGS thin-film solar cells are one of the most promising second-generation solar cells available. Its advantages include direct energy gap, excellent band manipulating and flexibility. The highest conversion efficiency is currently 23.35%, and the process used is sulfurization after selenization(SAS). In addition to sulfurization, silver alloying is also considered to be a promising way to improve efficiency. However, most of the research on silver addition is limited to selenization and co-evaporation, and little research is done on the sulfurization after selenization process.
In this study, a thin AgGa film was deposited in the precursor layer by sputtering, and a silver alloy with a surface sulfidation of (Ag,Cu)(In,Ga)(Se,S)2 absorber layer was produced by selenization followed by sulfurization. The effect of silver on the SAS process was investigated by making specimens with high and low silver content. It was shown that the Cu,Ag distribution of the sulfided specimens changed, resulting in a change in the energy band matching. The addition of a small amount of silver tends to produce an OVC phase in the specimen, which also changes the interface match.
Finally, by adding 10% silver, the device efficiency can be obtained up to 15.2%.

第1章 緒論 研究動機與目的 7
第2章 文獻回顧 8
2.1 太陽能電池工作原理 8
2.2 太陽能電池物理 8
2.2.1 PN接面二極體 8
2.2.2 PN接面的光伏效應 9
2.3 電流-電壓曲綫 (I-V curve) 10
2.3.1 開路電壓 10
2.3.2 短路電流 10
2.3.3 填充因子 10
2.3.4 光電轉換效率 10
2.4 銅銦鎵硒（CIGSe）太陽能電池 10
2.4.1 銅銦鎵硒（CIGSe）的晶體結構 11
2.4.2 銅銦鎵硒本質摻雑物理 11
2.5 CIGSe的太陽能電池製程 12
2.5.1 共蒸鍍製程（co-evaporation） 12
2.5.2 合金後硒化製程 12
2.5.3 硫化製程 13
2.6 能帶工程 13
2.7 硫化對CIGSe吸收層的影響 16
2.8 添加銀合金化 18
第3章 實驗流程與分析 25
3.1 吸收層製備 25
3.1.1 真空濺鍍鍍膜技術 25
3.1.2 硒化製程（selenization） 25
3.1.3 硫化製程（sulfurization） 25
3.2 元件製作 26
3.2.1 化學水浴法製備緩衝層 26
3.2.2 濺鍍鍍窗口層 26
3.2.3 蒸鍍鍍製上電極 26
3.3 材料分析方法與設備 27
3.3.1 X射綫螢光光譜分析 27
3.3.2 X射線光電子能譜分析 28
3.3.3 歐傑電子能譜儀分析 29
3.3.4 掃描電子顯微鏡分析 29
3.3.5 X射綫繞射儀分析 30
3.3.6 拉曼光譜儀分析 31
3.3.7 電流-電壓特性量測 31
3.3.8 外部量子效率量測 32
第4章 實驗結果與討論 34
4.1 第一部分 添加銀之純硒化試片 34
4.1.1 表面形貌 34
4.1.2 元件表現 35
4.2 第二部分 高銀含量硫化之試片(AAC50) 36
4.2.1 硫化後表面形貌 36
4.2.2 XPS縱深分析 36
4.2.3 銅銀反轉成因探討 38
4.2.4 高銀含量硫化電性表現 39
4.3 第三部分 較低銀含量硫化之試片 40
4.3.1 表面形貌 40
4.3.2 相分析 41
4.3.3 硫化後的元件電性 46
第5章 結論 48
第6章 參考文獻 49

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