在本論文中，有機電激發光二極體使用PET為基板，並採用真空熱蒸著技術成長元件。可撓式有機發光二極體的結構為PET/PHEMA 20K/Ag(20nm)/NPB (40nm)/ Alq3:C545T 1wt%(30nm)/Alq3 (30nm)/LiF (0.5nm)/Al (200nm)。由於從實驗中可知利用ITO當作可撓式有機電激發光二極體的陽極效能不佳，所以利用延展性較好的銀為陽極，NPB為電洞傳輸層材料，Alq3:C545T 作為綠光發光層材料，其中Alq3為主發光體材料，C545T為客發光體材料，同時Alq3亦做為電子傳輸層材料，Al當作反射陰極。較特殊的地方在於使用分子量為兩萬的PHEMA當作銀陽極跟PET基板之間的緩衝層，加入此層可有效的使銀陽極薄膜表面的品質提升，同時降低銀陽極表面的片電阻，可使得整體元件的起始電壓降低，進而增加元件的整體效能，與單純只有銀薄膜陽極的元件相比，加入分子量兩萬的PHEMA為緩衝層可將最大亮度提升88%，電流效率提升了42%，同時利用彎曲測試可知道加入了緩衝層可有效的增加可撓式有機電激發光二極體的可彎曲度。

In the thesis, a high flexibility, low sheet resistance flexible OLEDs with a PHEMA buffer layer grown on silver/PET substrate were successfully demonstrated. The structure based on PET/PHEMA 20K/Ag (20nm)/NPB (40nm)/Alq3:C545T 1wt%(30nm)/Alq3 (30nm)/LiF (0.5nm)/Al (200nm) was proposed.
The ITO/glass device and ITO/PET device were compared. The performance of ITO/PET device is much worse than ITO/glass. At the same time, silver as anode was used to compare with ITO/PET device, the maximum luminance increases 203% and luminous efficiency increase 30%. According to the above results, on the PET substrate, using silver as anode is better than using ITO as anode. PHEMA as buffer layer was used to increase the quality of silver film. It can decrease the sheet resistance effectively and increase the performance. To compare with Ag/PET device, the maximum luminance of Ag/PHEMA 20K/PET device increases 88% and luminous efficiency increases 42%. The flexibility of flexible OLEDs can be tested by bending the device. The bending test shows that the flexibility of ITO/PET device is lowly, and the flexibility of Ag/PHEMA 20K /PET device is highly. According to bending test, a highly flexible, luminance, and low sheet resistance device by using PHEMA 20K as buffer layer was succeed in fabricating.

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