本研究透過加入長鏈有機陽離子鹵化物於三維鈣鈦礦前驅液中，使其鈣鈦礦結構能夠轉換成為準二維結構。並利用光學顯微鏡、掃描式電子顯微鏡、原子力顯微鏡、吸收光譜與光致發光光譜等設備以研究其薄膜特質。結果證實，長鏈有機陽離子鹵化物的引入會使得鈣鈦礦的晶粒變小，以至於其放光光譜有藍移的現象。並與三維結構之鈣鈦礦相較而言，擁有更加平整且無孔隙的鈣鈦礦薄膜。
元件方面，長鏈有機陽離子鹵化物的加入會使得鈣鈦礦元件的外部量子效率從0.04%上升至1%。研究中更透過阻抗量測等分析來瞭解效率提升之原因。本研究更透過調整電洞注入層、電洞傳輸層、電子傳輸層、電子注入層等的厚度來將元件效率最佳化，使之能夠達到2%的外部量子效率。此外，為了減少元件製作成本以利商業化，除了利用熱蒸鍍的方式製備電子傳輸層，也用旋塗的方式製作。本研究證實以旋塗方式製備電子傳輸層的元件效率與使用熱蒸鍍方式製備的元件效率沒有太大的差異。更進一步的，本研究證實透過對電洞傳輸層的摻雜，能夠免去鈣鈦礦旋塗製程前所需要的電漿處理步驟，除了免除經過電漿處理對電洞傳輸層造成傷害之疑慮，並且所得到的元件效率與透過電漿處理的元件效率也不會差異太多。

In this study, by introducing long-chain organic cation halide to the precursor solution of three-dimensional perovskites, the crystal structure can be converted to a quasi-two-dimensional structure. Optical microscope, scanning electron microscope, atomic force microscope, absorption spectroscopy, and photoluminescence spectroscopy were used to study the properties of the perovskite films. Comparing with the undoped perovskite films, the perovskite films with long-chain organic cation halide showed blue-shifted photoluminescence peak, smaller crystal size, and smoother surface.
As for the perovskite light emitting diodes, the addition of long-chain organic cation halide improved the external quantum efficiency from 0.04% to 1%. Impedance spectroscopy was used to understand the underlying mechanism. Besides, the device performance was optimized by tuning the thickness of the hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer. The external quantum efficiency of 2% was obtained. Furthermore, for the commercialization purpose, spin coating was used to replace thermal evaporation to reduce the manufacturing cost of the electron transport layer. It was observed that the performance of the device with spin-coated electron transport layer is comparable with the one of the device with thermal-evaporated electron transport layer. Moreover, a conventionally used plasma treatment on the hole transport layer was replaced by doping organic molecules into the hole transport layer. Similar device performance was obtained without the worry of the side effect of the plasma treatment.

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