本篇論文主要探討以高分子材料聚[1-甲氧基-4-(2’-乙基-己氧基)-2, 5-苯乙烯]為主動層之紅光元件透過不同退火方式改善元件之效率與表現。在本篇論文中，根據聚[1-甲氧基-4-(2’-乙基-己氧基)-2, 5-苯乙烯] 的吸收光譜範圍位於綠光波段，因此我們使用波長532奈米的綠光雷射作為雷射源，針對發光層搭配不同的雷射退火條件探討有機高分子發光二極體的物性與元件表現。
在我們的實驗中，主要針對玻璃基板和可撓式基板(聚對苯二甲酸乙二酯)製作單層聚[1-甲氧基-4-(2’-乙基-己氧基)-2,5-苯乙烯]混合小分子電洞傳輸材料聯苯衍生物的元件，根據實驗的結果，我們發現雷射光處理不僅可以改善聚[1-甲氧基-4-(2’-乙基-己氧基)-2,5-苯乙烯]混合小分子電洞傳輸材料所造成的表面粗糙度，降低元件的驅動電壓，而且能提升光激發光的強度。此外，經由空間電荷限制電流法，我們也發現雷射光處理可提升主動層之電子的遷移率，增加載子的再結合效率，相較於加熱處理，雷射光處理可大幅提升元件整體效率。目前，針對玻璃基板而言，我們元件最佳的製備條件是雷射功率30 mW處理5分鐘，元件亮度可達4367 cd/m2，而元件效率可達1.85 cd/A；針對可撓式基板 (聚對苯二甲酸乙二酯)而言，最佳的雷射退火功率仍是30 mW，雷射退火處理10分鐘可達最佳的元件效率(亮度: 1888 cd/m2，效率2.61 cd/A)，熱與雷射同時退火處理10分鐘可達最佳的元件亮度(亮度: 2551 cd/m2，效率: 1.78 cd/A)。與其他團隊大部份所採用的加熱處理作元件比較之後，本論文重要的優勢在於我們發現雷射退火處理適合應用在低溫處理可撓式基板和可以節省一半以上的製程時間。

In this thesis, we concentrate on how to improve the performance of poly [2-methoxy-5- (2’-ethylhexyloxy)- 1,4-phenylene vinylene] MEH-PPV-based light emitting diodes by different methods of annealing. We adopted 532 nm green laser as the annealing source because the maximum intensity of MEH-PPV absorption spectrum is at the range of green light. In addition, we researched into the influence of emitting layer under different conditions of laser annealing which improve the physical property of emitting layer and device performance.
In our experiments, we blended MEH-PPV with (N,N’-diphenyl-N,N’-bis (1-naphthyl)-(1,1’-biphenyl)-4,4’-diamine) (NPB) as the emitting layer and fabricated single layer light emitting diodes of glass and Polyethylene terephthalate (PET) substrates. Based on the results of experiments, we find laser annealing can decrease the surface roughness, lower the turn-on voltage of devices and increase of PL intensity. Moreover, we can observe laser annealing can enhance the electron mobility in active layer and raise the possibility of carriers’ recombination efficiency. Compared with thermal annealing, laser annealing can improve the efficiency of device to a remarkable extent. For the device on glass substrate, the optimum parameter is 30 mW laser annealing for 5 minutes. Luminance is 4367 cd/m2 and current efficiency is 1.85 cd/A. Furthermore, for the device on PET substrate, the appropriate power of laser is still 30 mW. Laser annealing for 10 minutes can achieve the highest efficiency (luminance is 1888 cd/m2 and current efficiency is 2.61 cd/A) and simultaneous thermal and laser annealing for 10 minutes can realize the best luminance (luminance is 2551 cd/m2 and current efficiency is 1.78 cd/A). The most important advantage of this thesis is that laser annealing is suitable for low energy treatment and we can reduce the processing time by laser annealing when compared with thermal annealing.

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