摘?要 現今顯示器技術蓬勃發展，可應用於次世代顯示面版的有機發光二極體（OLED）已成為最具發展潛力的項目之一。其中高分子發光二極體（PLED）更具有製程簡單，成本低等優點。與小分子發光二極體比較，高分子發光二極體目前有操作電壓較高，發光效率較低，電極介面較差等問題。 本研究的主要目的是利用熱處理的方法來改善高分子發光二極體的缺點，並且探討未過濾的高分子材料溶液對元件發光效率的影響。實驗結果顯示，無論高分子發光二極體製作在玻璃基板或塑膠基板上，適當的熱處理確實可降低元件操作電壓，提高其發光效率，大幅改善元件的光電特性。另外，在元件製程中如使用未過濾高分子材料溶液可增加電子電洞的復合率，當外加電壓上升至一臨界電壓時，發現元件亮度有突然增加的現象。 利用適當的製程及熱處理方法，在玻璃基板上可獲得最佳的元件亮度高達436,000 cd/m2，其頻譜峰值為592 nm，電激光臨界電壓為6.4 V；在塑膠基板上最佳的元件亮度可達43,600 cd/m2，電激光臨界電壓為8.5 V，可忍受的曲率半徑達2 cm。 Abstract Since the thermal treatment (or annealing) is an important technique to control the morphology of poly(2-methoxy-5-(2’ethylhexoxy)-1, 4-phenylene-vinylene) (MEH-PPV) film, it has been employed in this study to improve the performances of MEH-PPV-based PLEDs fabricated on the glass or plastic substrate. The optimal thermal treatment condition could reduce the electroluminescence (EL) threshold voltage and enhance the brightness of a PLED. Also, the unfiltered powders of dissolved MEH-PPV played an important role affecting the device performance. They would confine the carriers and hence the recombination rate of electron-hole pairs could be enhanced. With the proper filtration process and thermal treatment condition, the device obtainable on glass substrate had a brightness (luminance efficiency) of 436,000 cd/m2 (130 cd/A) at an injection current density of 355 mA/cm2, and an EL threshold voltage of 6.4 V. Also, the device obtainable on plastic substrate had a brightness (luminance efficiency) of 43,600 cd/m2 (7.11 cd/A) at an injection current density of 600 mA/cm2, and an EL threshold voltage of 8.5 V.
