有機共軛高分子發光二極體由於製程簡單並可製作於大面積的面板上，因此近年來逐漸受到廣泛的討論與注意。然而有機共軛高分子材料容易受到水氣，氧氣影響而產生光氧化衰退現象進而嚴重影響元件壽命與特性。為了改善此不良影響，幾個改善元件特性的方法已被提出。其中，利用有機共軛高分子在旋轉塗佈成膜後以適當的溫度回火已被證明出有改善元件效率，發光亮度的效用。在這篇論文中，我們利用回火的方法，去找出高分子DBPPV的最佳回火溫度並針對回火完的薄膜與元件的特性加以討論。  
　　首先我們製作兩層結構（double layer structure）的有機高分子二極體（ITO/PEDOT/DBPPV/Al）。以導電薄膜PEDOT為電洞傳輸層(HTL)厚度約為150nm，DBPPV為發光層(EL)厚度約為130nm。在旋轉塗佈完DBPPV後，以六個不同的溫度分別為90˚C、110˚C、130˚C、150˚C、170˚C與190˚C回火。回火的溫度由低於DBPPV玻璃轉換溫度(Tg=120-130˚C)的90˚C到高於玻璃轉換溫度190˚C。因此，DBPPV的表面型態也隨著溫度改變。在隨著回火溫度的升高，DBPPV開始聚集(aggregate)，除了改變了DBPPV與陰極金屬的有效接觸面積之外並導致載子注入效率與發光效率的提升。但是，當回火溫度高於150˚C時，DBPPV部分側鏈(side chain)開始裂解，也因此導致元件的衰退。此外，我們也證明出以DBPPV為主的高分子發光二極體的最佳回火溫度為150˚C。
　　首先，以啟始電壓(turn on voltage)而言，回火150˚C的元件啟始電壓約為3.8伏。回火90˚C、110˚C、130˚C、170˚C與190˚C的元件啟始電壓分別為5.3、5.1、4.4、5.4與6.8伏。第二，在元件施加96毫安培時，回火90˚C、110˚C、130˚C、170˚C與190˚C的元件發光強度約為回火150˚C元件的0.6、0.8、0.9、0.9與0.7倍。第三，在施加40毫安培時，回火150˚C元件電流發光效率約為9.2 cd/m²-mA。其他元件則依序分別為8.4、8.9、7.5、6.6與5.3 cd/m²-mA (90˚C至190˚C)。
最後，回火150˚C元件的相對壽命約為回火110˚C、130˚C、170˚C元件的3.6, 2.6與 2.3倍。

　　Polymer light-emitting diodes PLEDs that are based on conjugated polymers have attracted much attention because of their potential applicability to large-area flat panel displays. While polymeric materials are known to be sensitive to moisture and oxygen, therefore, various approaches have been explored to improve the device efficiency, luminescence and its lifetime. One avenue that has only recently received attention is the thermal treatment of emitting polymer layers. In this work, an effect of thermal treatment before cathode deposition is presented for the purpose of determining the best annealing temperature for DBPPV.
　　During this research, the double layer structure had been made. (ITO/PEDOT/DBPPV/Al) The PEDOT (about 150nm) served as HTL and DBPPV (about 130nm) served as EL. Six kinds of device had been fabricated as a function of different annealing temperature. The organic polymer thin film tended to aggregate when the annealing temperature was above the glass transition temperature. This may result not only in the change of surface morphology but the barrier in the metal-organic interface, also. Therefore, the carrier injection efficiency was greatly affected in the same time.
　　The device annealed at 150˚C had been demonstrated to have better performance than others in the DBPPV based polymer light emitting diode. For example, the turn on voltage was about 3.8V of the 150˚C annealed device while the turn on voltage of device annealed at 90˚C, 110˚C, 130˚C, 170 ˚C and 190˚C were 5.3V, 5.1V, 4.4V, 5.4V and 6.8V, respectively. Besides, the device annealed at 150˚C had better relative luminescence and efficiency. The ratios of luminescence between different devices (from the 90˚C to 190˚C annealed devices) at the biased current 96mA to the 150˚C annealed device were 0.6, 0.8, 0.9, 0.9 and 0.7, respectively. Also, the current efficiency was 9.2 cd/m²-mA at the biased current 40mA while the others were 8.4, 8.9, 7.5, 6.6 and 5.3 cd/m²-mA (from the 90˚C to 190˚C annealed devices), respectively. Finally, the lifetime of 150˚C annealed device was 3.6, 2.6 and 2.3 times larger than the devices annealed at 110˚C, 130˚C and 170˚C, respectively.

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