有機-無機混合鈣鈦礦因為優越的材料特性，已被運用在不同功能的元件上，例如:發光二極體、太陽能電池、光感測器、電阻式記憶體…等元件。許多研究指出摻雜陽離子與陰離子可以提升鈣鈦礦太陽能電池性能，而卻無文獻研究在電阻式記憶體上的應用。
本論文研究分為兩部分。第一部分討論在一般的鈣鈦礦(MAPbI3)中摻雜不同濃度的甲脒氫碘酸(FAI)，研究其薄膜與元件特性的變化。由於甲脒(FA+)的離子半徑比甲胺(MA+)大，所以可以提高公差因子並誘導形成穩定的立方鈣鈦礦相，並增加薄膜的晶粒大小，降低晶界的邊際效應，提升鈣鈦礦主動層的吸光能力，使短路電流上升，致使太陽能元件的光電轉換效率提升。而在電阻式記憶體方面，由於FAI的添加可以穩定鈣鈦礦的晶體結構，改善元件的穩定度，致使記憶次數有明顯的提升。當摻雜75% 的FAI時，太陽能電池的轉換效率來到了10.8%，而電阻式記憶體則有100次左右的記憶次數。
第二部分則是將第一部分的最佳參數進行無機碘化銫(CsI)的微量摻雜，研究其薄膜與元件特性的變化。由於CsI的摻雜可以提升結晶性，形成高覆蓋率且緻密無孔洞的高品質鈣鈦礦薄膜，降低薄膜的缺陷，使開路電壓上升，致使太陽能元件的光電轉換效率提升。而在電阻式記憶體方面，由於CsI的添加可以改善薄膜品質，降低薄膜缺陷，因此可以穩定電阻式記憶體的on/off ratio。當摻雜5%的 CsI時，太陽能電池的轉換效率來到了14.2%，而電阻式記憶體則有120次左右的記憶次數及10的4次方左右的on/off ratio。

This research involves two parts. The first part discusses the effects of doping different concentrations of formamidinium iodide (FAI) into MAPbI3 perovskite on the properties of perovskite based films and photovoltaic devices. Since the ionic radius of formamidinium (FA+) is larger than that of methylammonium (MA+), the FA doping increases the tolerance factor and forms a stable cubic perovskite phase, enhancing the grain size of the film and reducing the marginal effect of the grain boundary that improves the light absorption of the perovskite layer. In the case of resistive random access memory (RRAM) device, the addition of FAI stabilizes the crystal structure of the perovskite, improving the stability of device that results in a significant increase in the number of memory cycles. When 75% FAI was doped in perovskite, the RRAM device performs about 100 memory cycles.
The second part of this thesis discusses the optimization of the parament characteristics of FAxMA1-xPbI3 perovskite that was doped with Cesium iodide (CsI). The crystallinity was improved by the CsI doping, and a high-quality and highly covered perovskite film with reduced defects. In the case of RRAM device, the on/off ratio can be stabilized. When 5% CsI is doped, the RRAM device has about 120 memory cycles and on/off ratio reaches 10000.

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