硫化鉛(100)晶面與有機鈣鈦礦(110)晶面有很好的晶格匹配度。故，本實驗計畫透過化學浴法製備出具有織構的硫化鉛薄膜，期望藉由此硫化鉛薄膜織構(優選方向)結構來控制有機鈣鈦礦(CH3NH3PbI3)薄膜優選方向。但經由實驗發現，不需控制硫化鉛(100)晶面，也能成長出具有織構的CH3NH3PbI3薄膜。
本論文研究分成兩部份，第一部份討論硫化鉛(Lead sulphide，PbS)緩衝層經由化學浴沉積法(chemical bath deposition，CBD)在不同基板上的沉積情況。接著，探討碘化處理的溫度、時間、碘片克數對硫化鉛緩衝層轉化為碘化鉛(Lead iodide，PbI2)薄膜的效應，由實驗發現影響硫化鉛轉化成碘化鉛，參數重要性為:碘片克數>碘化溫度>碘化時間。從實驗結果得知利用硫化鉛緩衝層所成長的碘化鉛與利用旋轉塗佈法所成長的碘化鉛，兩者表面形貌差異甚大。最後，透過爐管方式將MAI以低壓(1~2torr)環境下氣化，並探討MAI不同的氣化時間對CH3NH3PbI3表面形貌以及薄膜織構的影響。從實驗結果證實，確實經由硫化鉛緩衝層可製備出具有優選方向的 CH3NH3PbI3薄膜，其形成織構的原因為必須將CH3NH3PbI3晶粒尺寸提升，並發現在不同的基板(鉬玻璃基板與ITO玻璃基板)上織構表現會有差異，歸咎於基板本身具有優選方向所以加強了CH3NH3PbI3的織構表現。
第二部份分別將硫化鉛緩衝層所製備的與旋轉塗佈法所製備出的CH3NH3PbI3薄膜，製作成電阻式記憶體(RRAM)元件，結構為ITO/ CH3NH3PbI3/PMMA/Al，進行電性上的分析與探討。從實驗結果發現，CH3NH3PbI3薄膜厚度會影響on/off ratio，CH3NH3PbI3最佳膜厚約400nm此時on/off ratio達103，上層PMMA則為50mg/ml電性表現上最佳。我們發現具有織構的CH3NH3PbI3薄膜應用於RRAM整體漏電流的表現比旋轉塗佈法所製備的為低。

In this study, PbS buffer layer with (100) preferred orientation was deposited via chemical bath deposition (CBD) process. It is expected to control the orientation of the CH3NH3PbI3 thin film by incorporating the PbS buffer layer. The PbS buffer layer induced the preferential growth of CH3NH3PbI3 perovskite films (PbS-seeding process) involves three-step processes. a. PbS deposition: The PbS buffer layer was deposited via CBD method. b. PbI2 conversion: Iodization treatment of PbS to form PbI2. c. CH3NH3PbI3 conversion: Formation of CH3NH3PbI3 by simultaneous annealing and exposure to MAI vapor at low pressure. As compared to the spin-coating derived CH3NH3PbI3 thin film, the PbS-seeded growth of CH3NH3PbI3 thin film exhibited a larger grain structure, leading to a (110)-textured structure (Figure 1(a)). For comparison, the resistive random access memories (RRAM) were constructured by these two kinds of CH3NH3PbI3 film (PbS-seeding process and spin-coating process). Figure 1(b) shows a typical I-V characteristic of RRAM with the CH3NH3PbI3 thin film prepared by the PbS-seeding process.

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