鈣鈦礦在十年間於太陽能電池界中大放異彩，光電轉換效率已達22 %以上，近年於發光二極體中更有爆炸性的發展，用短短兩年時間已達有機發光二極體和量子點發光二極體發展十年的效能，外部量子效率已從1%提升到8%以上。本研究提出兩種電洞傳輸層材料使用於甲基氨基溴化鉛鈣鈦礦發光二極體中，其一是擁有優異穿透率和電洞濃度的p型半導體材料氧化亞錫，最重要的是其最高占據分子軌域(HOMO)與鈣鈦礦材料相近，可藉由控制製程時的氧通量與不同溫度的後退火處理來調整薄膜電洞濃度，製作出來的鈣鈦礦發光二極體亮度可達76,912 cd/m2，並擁有4.5 cd/A的電流效率。另一種材料為常用於有機發光二極體中的電洞傳輸層材料氧化鎳，在相同的旋塗法下，提升電流效率至6.06 cd/A。接著進一步提出改善發光層品質之方法，利用三明治結構的旋塗手法，讓反溶劑能完整包覆鈣鈦礦前驅物，使其快速成核，將晶粒成功縮小十倍以上，電流效率提升至10.35 cd/A。此外，若進一步嘗試製作雙層薄膜結構來修補針孔問題，從結果來看效果並不理想。於過去文獻中，還沒有使用氧化亞錫於發光二極體中的電洞傳輸層材料，本論文是第一個提出，而對於解決鈣鈦礦薄膜品質問題，都是使用添加化學藥品或需要特別的設備來完成，本研究只單純變換旋塗手法，即可達到相同效果。

Perovskite has yielded unusually brilliant results in the field of solar cells in recent 10 years, and its photovoltaic conversion efficiency has increased to 22 %. The external quantum efficiency (EQE) of perovskite light-emitting diodes (PeLED) has rapidly progressed from under 1% to over 8% in less than two years, and the current efficiency (CE) and luminance have approached the capability of quantum dots light-emitting diodes (QLED) and organic light-emitting diodes (OLED) which have developed for a decade. This research presents two kinds of materials which are used in the MAPbBr3 perovskite light-emitting diode for hole transport layer. One of them is SnO which has high transmittance and hole concentration. The most important is that its highest occupied molecular orbital (HOMO) level is about 5.8 eV which is very close to the MABr3. By adjusting different oxygen partial pressure (OPP) and annealing temperature, one can obtain different concentration of SnO. The luminance and current efficiency are 76,912 cd/m2 and 4.5 cd/A, respectively. Another material is NiOx which is used in OLED for transport layer commonly. The current efficiency is increased to 6.06 cd/A. Then the quality of the emission layer was further improved. Using the sandwich method, the antisolvent can completely sandwich the perovskite precursor and induce fast nucleation, so that the crystal grains are successfully reduced to 1/10 in size and the current efficiency is improved to be 10.35 cd/A. In addition, in order to repair the pinhole problem, the multilayer structure of emission layer was also developed. But the results were not ideal. In short, SnO was used as the material of hole transport layer for LED first time in this work. On the other hand, all of other studies always incorporate chemicals in the perovskite layer to improve its performance, but this work can achieve the same achievement by changing the spin coating method simply.

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