在OLED元件中，有一種發光型態是由不同的兩種分子受激發後組合而成，稱為激發複合態（exciplex）。其原理是利用最低的三重態能階相近之兩種材料混合作為發光層，此兩種有機材料一個利於電子傳輸，另一個則利於電洞傳輸；兩種材料分子受激發後因相近的激發態能階使電子雲疊合形成新的混成軌域，而電荷分別取自兩種不同分子之電荷傳輸層，產生新的放光能隙並放出不同的發光波長。
本論文包含兩大部分，第一部分為研究不同發光層蒸鍍率的OLED exciplex發光主體元件之特性，並結合各種分析手法輔助了解不同蒸鍍率之發光層物理特性及電性。第二部分為改善電子電洞的傳導平衡，使兩種電荷的激子產生區能準確地位於發光層內，避免不必要的載子浪費，使整體元件效能再提升。
由於exciplex發光能力與兩種不同分子的混合情況有關，因此為了使兩種有機分子在共蒸鍍時能極佳混合，本研究利用製程調控OLED元件的發光層蒸鍍率，探討改變蒸鍍率之exciplex發光層的各種特性，並結合量測結果盼能找出OLED元件運作機制，進而得到最佳的元件效能。找到了最佳的發光層蒸鍍率之後，本研究進一步透過改善元件電荷載子平衡，使得整體OLED元件效能可繼續往上提升。
實驗結果發現，改變發光層蒸鍍率的確影響OLED exciplex發光元件效能。
第一部分，本實驗選用的m-MTDATA與Bphen這組exciplex材料組合，在蒸鍍率為0.8 Å/s時發光層表面粗糙度最低、量測到的電容電壓值最大，製作的OLED元件效能在室內用亮度範圍500 nits以下表現最佳，其最高發光電流效率為61.0 cd/A，為參考元件的4倍左右。
第二部分本實驗利用單一載子元件比較，得知使用HTL: 22 nm與ETL: 30 nm的元件厚度能達到最佳的載子平衡，加上製程使用0.8 Å/s的發光層蒸鍍率，最終做出本研究的最佳元件。元件效能在發光強度440 cd/m2左右表現最佳，其最高發光電流效率為71.5 cd/A，並發出552 nm左右的EL光譜，適合製作省電元件。

In this thesis, we investigated the mechanism and characteristics of exciplex-based OLEDs by using m-MTDATA and Bphen because of the similar lowest triplet excited states as hole and electron transport organic materials with different emission layer process evaporation rates. We controlled emission layer process evaporation rates of OLED to make sure that two different electrical types of molecules were well-mixed. After that, we studied the improvement of carrier transport balance to make sure that carrier recombination region is accurately located in emission layer which helps to increase the use of excitons and improve OLED performance.
First part, we obtained better OLED efficiency of 61.0 cd/A with minimum surface roughness and maximum capacitive-voltage when evaporation rate was 0.8 Å/s. This value is increased by 4.1 times over the reported data. Secondly, we found that as using 22 nm hole transport layer and 30 nm electron transport layer we could get the most carrier balanced devices. At the same time, we obtained the best OLED efficiency of 71.5 cd/A in our study at a luminous intensity of 440 cd/m2.

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