銅銦鎵硒(Cu(In,Ga)Se2, CIGS solar cell)太陽能電池是太陽能電池產業中最具潛力的材料之一，生產時能源消耗為傳統矽基太陽能的一半，業界視為極具市場潛力的產品，目前太陽能板普遍採用矽基材或玻璃的太陽能板，由於重量重、不利於攜帶，所以現正在發展薄膜太陽能板及有機太陽能板的技術，將可減輕太陽能板的重量，並且具有軟的特性，可以捲曲、攜帶亦可降低製程成本。
本論文我們利用升溫鍍膜的方式，以單一四元靶及化合物靶、一階段共濺鍍且不需有額外硒氣氛的供給，於軟性的不銹鋼基板上鍍製CIGS吸收層，並完成元件。我們首先探討如何將吸收層轉移至不銹鋼基板上，能不受到不銹鋼所帶來的雜質影響，並探討其薄膜結構、電性；爾後，利用共濺鍍方式，同時提升開路電壓、短路電流及填充因子，進而提高元件效率。
在此研究中，我們藉由在吸收層內製作Normal Grading的方式，可有效將效率由最初的11%提升至超過14%。

The polycrystalline Cu(In,Ga)Se2 (CIGS) absorber is the most promising material for photovoltaics because of its highest conversion efficiency among all thin-film technologies. Moreover, by using stainless steel as substrates, the flexible CIGS thin film solar cells can be achieved by integrating roll-to-roll technique with high throughput and low thermal budget, leading to the low manufacturing cost and new market of flexible solar cells. Here, we fabricated high efficiency flexible CIGS solar cell by co-sputtering of quaternary CIGS target and GaSe2 target. The unique of this process is that the Ga profile and Ga content in CIGS films can be precisely controlled during the CIGS deposition, in addition, no any further post-selenization is needed. The various slope of Ga grading can be realized by simply tuning the sputtering condition of GaSe2 target. Back grading in CIGS solar cells is seen to improve device efficiency compared to ungraded device. This improvement is due to a field assisted carrier collection resulting in an improved EQE at long wavelength and passivation of the back contact recombination for the loss in FF and Voc. After optimization of Ga normal grading inside CIGS absorber, the highest efficiency of 14.28% (without anti-reflection coating) by using CIGS quaternary target on flexible substrate can be achieved with an open circuit voltage of 620 mV, short circuit current density of 30.64 mA/cm2 and fill factor of 75%.

第一章 簡介 8
1.1 銅銦鎵硒太陽能電池發展 8
第二章 文獻回顧 10
2.1 太陽能電池原理 10
2.1.1原理 10
2.1.2電壓電流特性 11
2.2薄膜性質探討 12
2.2.1成分組成 12
2.2.2結構特性 13
2.2.3缺陷種類 14
2.2.4吸收係數 16
2.2.5能隙範圍 17
2.2.6載子複合機制 18
2.3不鏽鋼基板 20
第三章 實驗 27
3.1試片製備 27
3.2實驗設備 28
3.3實驗流程 28
3.4分析儀器 29
第四章 結果與討論 33
4.1銅21%靶材鍍於不銹鋼基板CIGS性質 33
4.1.1不鏽鋼基板 33
4.1.2表面粗糙度 37
4.2改變鍍膜溫度對薄膜性質的影響 39
4.2.1薄膜成分 39
4.2.2晶體結構 41
4.2.3表面形貌 42
4.2.4電性分析 45
4.3能帶工程 47
4.3.1 Normal grading 47
4.3.2元件分析 50
第五章 結論 55
參考文獻 56

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