銅銦鎵硒薄膜太陽能電池因其具有能隙可調控性、高光吸收係數、極佳的室外穩定性、抗輻射能力等多項優勢，且有製作大面積、可撓性產品等市場潛力，而備受矚目。但在生產失業模組上，高製程溫度上一直是相當大的限制，一方面限制基板材料，進而無法降低成本或往可撓性產品發展，一方面產生大面積生產成分不均勻的問題。因此本論文提出添加銀元素與銅銦鎵硒硫合金化形成銀銅銦鎵硒硫薄膜太陽能電池，探討其在純硒化階段幫助晶粒成長形成大晶粒，同時降低吸收層晶界數目之現象，並如何影響硫化製程，在615℃的製程溫度下，轉換效率可達14.42%。並在在降低製程溫度45℃的情況下，發現銀銅銦鎵硒硫仍可在降低製程溫度的情況下，降低吸收層內部缺陷與介面缺陷，形成大晶粒與品質良好之吸收層，最後藉由調控H2S濃度，在570℃的製程溫度下，轉換效率可達14.51%之高轉換效率，遠遠超過未添加銀元素之元件。

Copper indium gallium selenide thin film solar cells have been paid special attention due to its tunable bandgap, high absorption coefficient, excellent outdoor stability, and radiation resistance, as well as the market potential of fabricating large-area and flexible products. However, the high process temperature has been a limitation in the commercial modules. On the one hand, the substrate material is restricted, thus the cost of CIGS modules cannot be reduced or the substitute substrate such as flexible substrates can not be developed. On the other hand, the issue of non-uniform composition in large-area module is rasied. Therefore, this thesis proposes the silver alloyed with Cu(In,Ga)(S,Se)2 thin film solar cells can help the grain growth in the selenization stage, reducing the number of grain boundaries in the absorber layer. Based on this result, we discuss how the number of grain boundaries affect the sulfurization process. As the results, the performance can reach to 14.42% at the process temperature of 615°C. In the second part, when the process temperature was lowered by 45°C, it was found that the ACIGSSe can still maintain the absorber quality and grain size with lower bulk and interface defects. By adjusting the concentration of H2S, the conversion efficiency can reach up to 14.51% at the process temperature of 570°C, which is higher than CIGSSe.

第一章 緒論 1
1-1 研究動機與目的 1
第二章 文獻回顧與探討 2
2-1太陽能光伏元件物理 2
2-2 電流密度-電壓曲線(I-V curve) 3
2-2-1 開路電壓 3
2-2-2 短路電流 4
2-2-3 填充因子 5
2-2-4 串聯電阻和並聯電阻 5
2-2-5 光電轉換效率 6
2-3 銅銦鎵硒薄膜太陽能電池元件結構 7
2-3-1 基板 7
2-3-2 背電極 8
2-3-3 吸收層 8
2-3-4 緩衝層 10
2-3-5 窗口層 12
2-4 銅銦鎵硒薄膜性質 13
2-4-1 銅銦鎵硒晶體結構 13
2-4-2 銅銦鎵硒本質摻雜物理 13
2-5 銅銦鎵硒薄膜太陽能電池材料選擇標準 15
2-5-1 電子親和力(Electron affinity) 15
2-5-2 量子轉換效率(Quantum efficiency) 15
2-5-3 載子複合速率 (Recombination rate) 17
2-6 銅銦鎵硒薄膜太陽能電池製程 18
2-6-1 三階段共蒸鍍製程(three-stage co-evaporation process) 19
2-6-2 合金後硒化製程(selenization process) 21
2-6-3 硫化製程(sulfurization process) 23
2-7 寬能隙太陽能電池 24
2-7-1 鎵摻雜寬能隙太陽能電池之限制 25
2-7-2添加銀元素合金化 28
第三章 實驗流程與材料分析方法 38
3-1 實驗流程與設計 38
3-1-1 實驗流程 38
3-2 材料分析與電性量測方法 40
3-2-1 X光繞射分析 (X-ray diffraction, XRD) 40
3-2-2 X光螢光分析 (X-ray fluorescence, XRF) 40
3-2-3 冷場發射式電子顯微鏡 (Scanning electron microscope, SEM) 41
3-2-4 X射線光電子能譜儀 (X-ray photoelectron spectroscopy, XPS) 41
3-2-5 光致螢光光譜 (Photoluminescence and time-resolved photoluminescence, PL and TRPL) 42
3-2-6 拉曼光譜儀 (Raman spectrometer) 42
3-2-7 太陽光模擬器與Keitheley4200系統 43
3-2-8 外部量子效率量測儀 44
第四章 結果與討論 45
4-1 添加銀元素合金化在硒化製程 45
4-1-1添加銀元素合金化在硒化製程之薄膜性質分析 45
4-2添加銀元素合金化在硒硫化製程 48
4-2-1添加銀元素合金化在硒硫化製程之薄膜性質分析 48
4-2-2添加銀元素合金化在硒硫化製程之電性分析 53
4-3 添加銀元素合金化降低製程溫度 59
4-3-1 添加銀元素合金化降低製程溫度之元件電性表現 59
4-3-2 添加銀元素合金化降低製程溫度之薄膜性質分析 64
第五章 結論與未來展望 65
第六章 參考文獻 66

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