本論文旨在於將有機發光二極體(organic light emitting diode, OLED)導入醫療光源的應用上，為了使光源能夠均勻的照射於肌膚，我們勢必將做成可撓式的元件，而要達成此一目的需要替換掉傳統的銦錫氧化物(indium tin oxide, ITO)陽極，取而代之的是多層合金(Al/ Al:Ag)陽極結構，以便我們在未來能實現此結構於可撓式的parelyne基板。由於金屬優異的導電特性，可大幅提升元件的電流並提高亮度，此外使用P型金屬氧化物摻雜的電洞注入層，可克服因離子化能量大而導致的電洞注入問題。利用激發錯合物(exciplex)的共主體系統可提高元件效率，exciplex主體能提高三重態激子的使用效率，實現高效率的主-客體間能量轉移。最終此ITO-Free元件之放光波長為628 nm，在此波長下的光源可促進頭髮生長並加速傷口癒合，亮度為100 cd/m2時驅動電壓為2.7 V，最大外部量子效率、電流效率及功率效率分別為17.1%、21.4 cd/A和25.3 lm/W，目前的研究成果已將此結構成功實現於發光區為20 × 20 mm的大面積玻璃基板上。OLED元件其具重量輕以及可撓性的特質，在穿戴式電子裝置的應用上，是極具發展潛力的前瞻技術之一。

The purpose of this thesis is to introduce organic light emitting diode (OLED) into photobiomodulation (PBM) applications. In order to make the light source irradiate evenly on the skin, we must make a flexible component. To achieve this goal, we replace the traditional indium tin oxide (ITO) anode with a multilayer alloy (Al/ Al:Ag) anode structure, so that we can realize this structure in the flexible parelyne substrate in the future. Due to high conductivity as well as low sheet resistant of metals, the current and brightness of our ITO-Free device can be greatly increased. In addition, the use of a hole injection layer doped with P-type transition metal oxide can overcome the problem of hole injection induced by high ionization energy. An exciplex cohost system is employed to utilize both singlet and triplet excitons to achieve high efficiency. Under the positive bias, carriers accumulate at the interface between donor and acceptor due to the different energy gap, and then directly combine with the red phosphorescent with almost zero energy loss. The obtained results of this ITO-Free device can achieve low turn-on voltage of 2.7 V at 100 cd/m2, and highly efficient of 17.1%, 21.4 cd/A and 25.3 lm/W corresponding to external quantum efficiency, current efficiency and power efficiency. Moreover, because of strong microcavity effect in this device, we can adjust the emission region to the specific wavelength by subtly tune the optical thickness. Finally, the emission wavelength peak is positioned at 628 nm, the emission within this range can have great benefit on hair growing and wound healing. The recent progress of this work already realized this structure based on a large area (20 × 20 mm) glass substrate. OLEDs with their properties of light weight, flexibility and high water vapor resistance of encapsulation, it is none doubt to be one of the most potential candidate for wearable electronics.

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