有機鈣鈦礦因為優越的光電及記憶特性，被運用在不同功能的方面，例:發光二極體、太陽能電池、光感測器、電阻式記憶體…等單一元件，期望能突破做出鈣鈦礦雙功能元件。許多研究指出摻雜鹼金屬提升鈣鈦礦太陽能電池性能，而卻無應用在電阻式記憶體上的文獻。
本論文研究分為兩部分。第一部分討論以CH3NH3PbBr3為主，發光二極體元件結構為基礎，改變鍍膜製程和電極大小，嘗試製作具備電阻式記憶體及發光二極體特性的雙功能元件。使用一步法來製備薄膜，經過在旋塗過程中滴定反溶液、吹氮氣，及改良吹氮氣的裝置後，薄膜表面形貌有大幅提升，但無法製作出平整均勻的薄膜，轉而以兩步法成功製作出均勻且平整的CH3NH3PbBr3薄膜。在每個嘗試改善薄膜的階段，發光二極體皆只出現大面積(6.5mm2)的電極上，而記憶體特性只出現小面積(0.01mm2)的電極上。TPBi從旋塗的方式改為熱蒸鍍來製備改善元件後，大小電極皆只有發光二極體的電壓電流特性而沒有記憶體特性。
第二部分討論的是在鈣鈦礦與ITO基板中間加入PEDOT:PSS修飾能階，提升記憶時間。在鈣鈦礦前驅溶液碘化鉛當中加入不同濃度的碘化鉀觀察其薄膜與電阻式記憶體特性的變化，鈣鈦礦材料是 CH3NH3PbI3，在摻雜5mg/ml及7mg/ml的碘化鉀後碘化鉛及有機鈣鈦礦薄膜表面形貌皆有改善，從PL intensity的提升能明確看到薄膜非複合缺陷態的減少，記憶體元件的切換次數從原本的45次增加到207次。而摻雜過量的碘化鉀，不僅使鈣鈦礦薄膜產生孔洞、PL和XRD強度下降，也讓元件的記憶次數下降到剩18次和on/off ratio從原本的103變為102。

In this study, we used anti-solvent and N2 flow treatment during the spin coating process to improve the film quality in a one-step method. It is very difficult to control the experimental parameters and film quality by dropping the anti-solvent during the spin coating process.
The N2 flow treatment during the spin coating process can significantly improve the film quality. Under the pressure of 8kgf/cm2, the film quality is improved compared with the film quality of 6kgf/cm2. Even if the film quality can be improved by increasing the pressure but the effect is limited.
In this study, we found that the incorporation of an appropriate amount of potassium iodide in lead iodide solution can improve the lead iodide film, and also significantly improve the perovskite film reduce the defects of the film after the formation of perovskite.
After adding PEDOT:PSS in the middle of perovskite and ITO, the energy level and passivation surface can be modified so that the carrier can be injected into the active layer more smoothly, and the on/off ratio is slightly improved. It was found that the number of switching endurance of RRAM device incorporated with 7 mg/ml potassium iodide was increased from 45 times to 207 times.

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