在本篇論文，我們提出了一具有使用碳化矽窗口層之新穎性交疊式奈米柱HIT太陽能電池架構(A New Interdigitated Nanopillar HIT Solar Cell by Using Silicon-Carbide-based Window Layer, INSC-HIT)。在此研究中，我們以非晶矽與單晶矽作為異質接面的主軸，其中非晶矽能隙在1.7 eV到1.9 eV之間，有較強的光吸收係數，單晶矽能隙約為1.12 eV，具有載子擴散長度較長之優點。且分別可以針對太陽光譜較短部分以及較長部分的波長進行吸收，同時達到吸收各個不同波段的波長，改善內部量子效率與外部量子效率。再結合新穎性奈米柱獨特的特性，除了抗反射能力、載子捕捉、逕向分離機制、延長吸收區域等，使入射光在奈米柱之間散射，進一步提升光子被吸收能力，增進短路電流密度。此外，還具有較大的電場分佈範圍，讓載子被電場涵蓋的範圍變大，使載子加速移動，減少到達電極前被復合的機會。此時，再沉積一層本質非晶矽鈍化層，降低因奈米柱延長表面積，所導致的表面復合速率增加，進而提升太陽能電池的轉換效率。此新架構模擬結果，轉換效率可以達到25.69 %，相較於目前傳統最高效率的平面式HIT太陽能電池(24.7 %)可提高3.85 %的轉換效率。另外，為了再次提高轉換效率，我們針對表面電極ITO與a-Si之間進行分析，發現存在著損失比例佔相當大的寄生光吸收損失。因此將窗口層p+-a-Si改為p+-a-SiC材料，其材料優點具有較寬之能隙(1.9~2.6 eV)、較高之導電性、較好之透光性、能降低與電極間之寄生光吸收損失。並使用模擬軟體進行厚度最佳化設計，結果我們發現在相同太陽能電池結構下，窗口層採用碳化矽材料可達到26.09 %的轉換效率。
本論文中，我們架構不需要使用交指式背電極IBC太陽能電池就能改善遮蔭效應和寄生吸收損失。為了因應低成本、高效能太陽能電池的發展趨勢，此新穎的架構，不僅製程相當簡單，且只需要一片光罩，就能完成此架構。不同於把電極製作在背後，導致製程相當繁雜，且成本上升。

In this paper, a New Interdigitated Nanopillar HIT Solar Cells using Silicon-Carbide-based window layer (INSC-HIT) was proposed. By using Silvaco TCAD simulation, we demonstrated that the characteristics of it are significantly improved. The Interdigitated Nanopillar performance can enhance the light absorption, the antireflection behavior, and the light scattering significantly. The electric field region is large enough to ensure that the photo-generated carriers can reach the contacts without significant recombination. The area of the depletion region of Interdigitated Nanopillar is higher than that of traditional one, which cans benefit photon absorption. In addition, using Silicon-Carbide-based window layer is able to enhance the short-circuit current density by reducing the parasitic absorption losses in the ITO and a-Si layers without degrading the electrical performance of the device and reflection loss. Also, we can cut the required c-Si wafer thickness more than that required for the convention c-Si wafer in heterojunction solar cells thereby reducing the cost. By using silicon nanopillar the light absorption can be enhanced thus we can reduce c-Si wafer thickness and the total cost. The maximum short-circuit current density of 42.12 mA/cm2 is achieved. And, the conversion efficiency of INSC-HIT is 26.09 % which is higher than that of the conventional planar HIT solar cell (24.7 %).

論文審定書 i
英文論文審定書 ii
致謝 iii
中文摘要 iv
英文摘要 v
第一章、導論 1
1.1. 研究背景 1
1.2. 文獻回顧 3
1.3. 動機 7
第二章、元件製作 9
2.1. 模擬元件 9
2.1.1 使用碳化矽於窗口層之新穎性交疊式奈米柱HIT太陽能電池模擬 9
2.1.2. 模擬之物理模型與參數 10
2.2. 元件實作 12
2.2.1新穎性交疊式奈米柱HIT太陽能電池製程 12
2.2.2. 製程與光罩設計 12
第三章、模擬結果與討論 15
3.1. 傳統HIT太陽能電池 16
3.2. 新穎性交疊式奈米柱HIT太陽能電池 19
3.2.1. 模擬之最佳化 21
3.3. 使用碳化矽於窗口層之新穎性交疊式奈米柱HIT太陽能電池 40
3.3.1. 模擬之最佳化 42
3.4. 使用碳化矽於窗口層之新穎性交疊式奈米柱HIT太陽能電池插入一層非晶碳化矽本質層 45
3.5. 各類型太陽能電池最佳化結果之邊際效應比較(Benchmark comparison) 50
3.6. 實作量測結果與討論 53
3.6.1 新穎性交疊式奈米柱製程結果與討論 53
3.6.2 新穎性交疊式奈米柱太陽能電池量測 54
3.6.3 對照組傳統HIT太陽能電池量測 56
第四章、結論與未來展望 58
4.1. 結論 58
4.2. 未來展望 59
參考文獻 60
附錄A 68
光電效應 68
光伏特效應 69
太陽光譜 70
太陽能電池原理 73
太陽能電池的電性參數 74
光學特性探討 77
外部量子效率 78
內部量子效率 78
復合機制 79
蕭克力萊德霍爾復合(SRH recombination) 79
輻射復合(Radiative Recombination) 80
歐傑復合(Auger recombination) 81
太陽能電池的效率損失及提升 81
抗反射層與透明導電膜 82
論文著述 84

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