鈣鈦礦太陽能電池因具有高光吸收係數、可調控能隙及低溫製程等優勢，近年來成為高效率光伏元件的重要研究方向。然而，蒸鍍-溶液法製備之鈣鈦礦薄膜仍可能受到晶界缺陷、界面復合及退火時間影響，導致載子非輻射復合增加，進而限制元件開路電壓（VOC）與光電轉換效率（EQE）之提升。因此，本論文針對晶界、電極界面與退火製程進行優化，以改善鈣鈦礦薄膜品質與元件光電特性。
本研究首先導入 PAD 作為晶界鈍化添加劑，以促進晶粒成長、改善薄膜結晶品質並降低晶界缺陷，進而提升單接面元件（single-junction device）性能。另一方面，探討 PDADI 作為電極界面鈍化材料之影響，藉由抑制非輻射復合損失並改善界面電性，提升界面傳輸特性。
最後，將最佳化之晶界鈍化、電極界面鈍化與退火製程條件應用於鈣鈦礦/矽串聯太陽能電池。結果顯示，經最佳化處理後之串聯元件獲得 29.02% 之光電轉換效率。研究結果證實，晶界與電極界面鈍化策略結合退火製程優化，可有效提升蒸鍍-溶液法鈣鈦礦太陽能電池之 VOC 與元件效率，並展現其應用於高效率鈣鈦礦/矽串聯太陽能電池之潛力。

Perovskite solar cells have emerged as an important research direction for high-efficiency photovoltaic devices in recent years owing to their high optical absorption coefficient, tunable bandgap, and compatibility with low-temperature fabrication processes. However, perovskite films fabricated using the evaporation-solution method may still suffer from grain-boundary defects, interfacial recombination, and the effects of annealing duration, resulting in increased non-radiative carrier recombination and consequently limiting improvements in the open-circuit voltage (VOC) and power conversion efficiency (PCE) of the devices. Therefore, this thesis focuses on optimizing the grain boundaries, electrode interface, and annealing process to improve the quality of perovskite films and the photovoltaic performance of the resulting devices.
First, PAD was introduced as a grain-boundary passivating additive to promote grain growth, improve the crystallinity of the perovskite films, and reduce grain-boundary defects, thereby enhancing the performance of single-junction devices. In addition, PDADI was investigated as an electrode-interface passivation material. By suppressing non-radiative recombination losses and improving the interfacial electrical properties, PDADI enhanced charge transport across the interface.
Finally, the optimized grain-boundary passivation, electrode-interface passivation, and annealing conditions were applied to perovskite/silicon tandem solar cells. The optimized tandem device achieved a PCE of 29.02%. These results demonstrate that combining grain-boundary and electrode-interface passivation strategies with annealing-process optimization can effectively improve the Voc and device efficiency of perovskite solar cells fabricated using the evaporation–solution method, highlighting the potential of these strategies for application in high-efficiency perovskite/silicon tandem solar cells.

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