為因應世界能源短缺，可重複使用、乾淨的能源為下一世代考量的重點。 CIGS為第二代薄膜太陽能電池，具有高吸收係數、能源回收期短短、成本低廉及高穩定性等競爭優勢。德國ZSW已發展出效率21.7%之高效率CIGS太陽能電池，其未來應用於市場之潛力十分龐大。
電漿用於太陽能電池上早有文獻出現，有研究指出硒粒加熱形成硒蒸氣時容易造成Sen (2<n<8)的環狀或鏈狀原子團的結構，因為這些結構較低的反應，在硒化的過程容易有硒化不完全問題，多的二次相的生成導致Ｖoc和Jsc的下降，因此元件的轉換效率下降.在電漿中，高能的電子可以斷開硒原子間的鍵結，使其形成擁有較高反應能的單一硒原子，借此解決硒化不完全的問題，而使效率得到提升。這種效果也可以降低製程溫度，在相對較低的溫度下得到高效率可以大幅地降低製程成本，也是電漿應用在CIGS太陽能電池上最重要的利益。
本實驗使用合金後硒化(post selenization)退火的方式製作CIGS太陽能電池。再玻璃基板上製備完前驅物後送入硒化爐硒化,然後再升溫曲線不同的步驟中加入電漿，也嘗試著改變電漿的瓦數，測試出最佳的硒化參數以達到高效率的元件。
而電漿的低溫製程效果也被我們拿來應用在以不銹鋼為基板的軟式太陽能電池上，不鏽鋼基板中的鐵雜質容易在硒化過程中擴散進入CIGS的吸收層中形成缺陷或其他化合物，導致元件效率下降，但是低溫的製程可以抑制雜質擴散，也可以降低雜質阻隔層的厚度。
而電漿的低溫製程效果也被我們拿來應用在以不銹鋼為基板的軟式太陽能電池上，不鏽鋼基板中的鐵雜質容易在硒化過程中擴散進入CIGS的吸收層中形成缺陷或其他化合物，導致元件效率下降，但是低溫的製程可以抑制雜質擴散，也可以降低雜質阻隔層的厚度。
現行已開發電漿輔助製程方式製備大面積(30cm*40cm)合金後硒化CIGS太陽能電池，並且成功達到13%之效率，不鏽鋼的軟式太陽能電池(不含鈉)也可以在大面積下達到6 %之效率。此方法於工業應用上有十分龐大之潛力及前景。

For the sake of energy shortage, renewable and clean energy substitution is a considerable point for the next generation. CIGS is the best thin film solar cell among the second generation solar cells owing to its various outstanding behaviors, such as the highest absorption coefficient, the easiest integration with Si-based technology and the highest efficiency in thin film solar cell. Therefore, it has already attracted tremendous attention in academic and industrial fields. Up to date, the highest efficiency of ~21.7% has been demonstrated by ZSW in Germany.
Plasma application on solar cell has been researched by many groups. It has been found that Se vapor is easily formed as Sen, which is ring or train structure (2<n<8).These structures have low reactant energy, resulting in the problem of incomplete selenization. In this thesis, a progressing non-toxic plasma-enhanced solid Se vapor selenization process (PESVS) technique, compared with hydrogen-assisted Se vapor selenization (HASVS) to achieve a large-area (40x30 cm2) Cu(In,Ga)Se2 (CIGS) solar panel with enhanced efficiencies from 10.8 % to 13.2 % (14.7 % for active area), was demonstrated. The bonding of Se was partially broken by ICP plasma treatment and these Se radicals are helpful to enhance reaction activity for following selenization process at an extremely low temperature of 330 ˚C. The effects of plasma steps, plasma power, selenization temperature and optimized conditions were thoroughly studied in detail. The remarkable enhancement of the efficiency is ascribed to the better crystallinity, enlarged grain size, less Se vacancy and uniform depth distribution of Ga. From reaction kinetics point of view, PESVS provides extra energy to crack Se, resulting in the decrease in reaction activation energy. The PESVS methodology was also applied to low temperature (450 ˚C) selenized CIGS thin film solar panel with uniform conversion efficiency more than ~10 %. Furthermore, a large-area flexible stainless steel substrate with remarkable conversion efficiency of ~6.8 % without Na addition was demonstrated. We believed that this work can provide a facile approach of low temperature selenization on flexible substrate applications or fast selenization for throughput consideration, thus stimulating the mass-production in large scale CIGS PV industry.

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