鹵化物鈣鈦礦太陽能電池近幾年來快速的發展，為了未來於商業化上的應用，除了追求高光電轉換效率外，穩定性也成為了很重要的議題，現今高效率的鈣鈦礦太陽能電池多使用有機無機混成之鈣鈦礦，但其包含有機陽離子如甲基胺或甲脒胺，使得鈣鈦礦在熱穩定與溼氣穩定性仍然還有很大的挑戰。
本論文使用銫離子取代甲基胺合成全無機鈣鈦礦CsPbIBr2，主要探討退火溫度對CsPbIBr2無機鈣鈦礦的影響，而鈣鈦礦的製備方式主要為一步溶液工程法，而無機鈣鈦礦之優點主要在於熱穩定較佳，本論文利用兩階段的退火方式，並藉由吸收圖譜、光致放光圖譜與X光繞射分析儀，分析溫度對CsPbIBr2薄膜光學性質及膜的品質的影響，再利用電子顯微鏡與聚焦離子束，觀察薄膜的表面形貌與厚度，結果顯示第一階段溫度主要影響薄膜的緻密性，第二階段主要影響結晶性、穩定性與晶粒大小，在前段溫度60°C與80°C下有較好的覆蓋率，藉由電子顯微鏡計算出的平均粒徑，與X光繞射分析儀計算特定繞射峰的半高寬，顯示在高溫下有較大的晶粒產生。在穩定性方面，於濕度70±5%未照光的情況下，低溫退火與高溫退火對鈣鈦礦穩定性有著明顯差異，可直接從肉眼明顯觀察到膜的變化，而在量測光致放光時，隨著量測時間越久，除了原有的光致放光波長外，會偵測到更長波長的訊號，主要是照光引致富含碘與富含溴的鈣鈦礦相分離，此現象是可逆的。最後於元件表現上，比較CsPbIBr2於多孔結構與平板結構上之差別，由電子顯微鏡發現鈣鈦礦無法完全進入到多孔氧化物載子傳輸層，降低元件的開路電壓與短路電流之，將多孔載子傳輸層改為平面型載子傳輸層作為平板型元件，提升鈣鈦礦與載子傳輸層的接合(junction)，提升元件光伏表現，在80-250°C組合中，光電轉換效率達到7%。

In this study, we used two-step thermal process to fabricate the CsPbIBr2 thin film. We adjusted the first step annealing temperature to control thin film surface coverage, and control grain size and film quality by second-step annealing. However, the contact between m-TiO2 and perovskite is poor or perovskite can’t be penetrated in the mesoporous TiO2. According this reason, the performance of the mesoporous device is not reproducible. We decided to use planer structure to replace mesoporous device. Finally, it improved open circuit voltage and efficiency. We achieved the best efficiency about 7% at 80-250°C at first and second step, respectively.

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