本實驗主要研究鈣鈦礦發光二極體中的P型電極介面層，在先前的研究中，本實驗室提出一個以純物理研磨的方式製備氧化鎳奈米粒子(NiO Nanoparticles)，其尺度達到數十奈米等級，後將其應用在太陽能電池中作為取代PEDOT:PSS電洞傳輸層之角色並達到13%的效率。在本論文中改進其研磨方式後，以噴塗的方式讓製程更加快速且穩定，並且成膜特性上表現更加的完善。相較於溶膠凝膠法(sol-gel)的氧化鎳電洞傳輸層製備方法，以及先前研究所提出的以旋轉塗佈溶液之製程，噴塗能有更好的表面均勻性、更快速且穩定的製程，同時其平均亮度能達到21,000 cd/m2，並且於大面積元件下仍舊有穩定的成膜特性，於未來發展有良好的前景。
本篇論文中我們將對以研磨製程製備的Grinding NiO NPs進行多種材料特性之量測及分析，例如：粒徑分析、能階分析、元素分析，接著多方面比較此研磨製程與先前研究之氧化鎳製備方試做比較，例如：薄膜形貌分析、光致發光、AFM、SEM，並成功以此噴塗製程製備出一大面積 下仍能均勻複合放光之鈣鈦礦發光二極體。

SUMMARY
During this thesis, we will focus on p-type electrode-interlayer of perovskite light-emitting diodes. In a previous research, we mentioned a physical grinding method as the precursor solution preparation of nickel oxide nanoparticles which can get a uniform solution with less than one hundred nanometer of the particle size and reach 13% by substituting PEDOT:PSS as the HTL in organolead iodide perovskite-based solar cell. By utilize the spray coating method, we can get a very uniform nickel oxide hole transporting layer and successfully apply it as the HTL into light-emitting diodes to substitute sol-gel NiOx. With this fast, low cost and low temperature process comparing to the traditional sol-gel NiOx which needs a high temperature condition to form the film, we can finish the HTL in even 1 minute without annealing and still reach the maximum brightness 21,000 cd/m2.
We study several physical properties of grinding NiO NPs such as partical size, UPS, XPS and XRD analysis. Furthermore, we take a detail comparison of sol-gel NiOx, PEDOT:PSS and grinding NiO NPs such as thin film, PL, AFM, SEM and TRPL analysis. Finally, we successfully demonstrate a NiO NPs based device which can reach the maximum brightness 21,000 cd/m2. In addition, it only cost one minute to form the film and without any annealing. With the process mention in the above section, we can also successfully build large area light-emitting diodes devices and light up uniformly.

Introduction
In conventional planar heterojunction solar cell, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate which is known as PEDOT:PSS is the most common used material as a hole transporting layer(HTL). PEDOT:PSS has the weak point that it’s an acid material which may lead to a corrosion to the indium tin oxide(ITO). Also, PEDOT:PSS contains hydrogen monoxide which may stongly affect our active layer, also known as perovskite, which is very sensitive to moisture. According to improve this issue, J. Y. Jeng et al. and the group successfully substitute PEDOT:PSS by nickel oxide (NiOx) and act as a hole transporting material and apply into planar heterojunction perovskite solar cells.
NiOx is kind of material which has the characteristics that can block the electron from passing through it, an inorganic material that maybe more stable, good energy level which fits the active layer. Knowing that the process of the NiOx that researchers follow recently are mostly contain complex steps, such as high temperature, high vacuum condition and chemical synthesis, which may lead to some uncertain factors that will affect the device intensely.

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