研究生: |
蔡博安 Po-An Tsai |
---|---|
論文名稱: |
高效率激發錯合體摻雜紅色螢光材料之有機發光二極體 Fabrication of A Highly Efficient Exciplex Based Red Fluorescent Organic Light-Emitting Diode |
指導教授: |
李志堅
Chih-Chien Lee |
口試委員: |
劉舜維
Shun-Wei Liu 張志豪 Chih-Hao Chang 范慶麟 Ching-Lin Fan 李志堅 Chih-Chien Lee |
學位類別: |
碩士 Master |
系所名稱: |
電資學院 - 電子工程系 Department of Electronic and Computer Engineering |
論文出版年: | 2019 |
畢業學年度: | 107 |
語文別: | 中文 |
論文頁數: | 88 |
中文關鍵詞: | 有機發光二極體 、激發錯合體 、熱活化延遲螢光 、反向系統間跨越 、元件壽命 、暫態光致發光 、暫態電致發光 |
外文關鍵詞: | OLED, Exciplex, TADF, RISC, Lifetime, Transient Photoluminescence, Transient Electroluminescence |
相關次數: | 點閱:377 下載:0 |
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本論文以carbazole結構之電洞傳輸材料4,4′,4″-tri(Ncarbazolyl)triphenylamine (TCTA)做為電子施體,以及triazine結構之電子傳輸材料2,4,6-tris(3-(1H-pyrazol-1-yl)phenyl)-1,3,5-triazine (3P-T2T)做為電子受體,使用共蒸鍍的方式混和兩種材料,使得在膜層介面上形成高效率的激發錯合體,並從光致發光光譜證明激發錯合體的產生。
接著透過結構上的調變,分析結構對效率之影響,並最佳化元件使載子達到平衡,綜合了結構調變的實驗結果,激發錯合體元件得到12%的高外部量子效率,而在激發錯合體中摻雜5%的紅色螢光材料得到9.2%的高外部量子效率。
最後,在壽命量測實驗中,以1000 nits的初始亮度,得到T75的元件壽命為310分鐘,也利用暫態光致發光及暫態電致發光印證激發錯合體的機制。
In this work, we used carbazole based hole transport material 4,4′,4″-tri(Ncarbazolyl)triphenylamine (TCTA) as electron donor and triazine based electron transport material 2,4,6-tris(3-(1H-pyrazol-1-yl)phenyl)-1,3,5-triazine (3P-T2T) as electron donor in an exciplex forming OLED. The two materials were mixed in a co-vapor deposition method to produce highly efficient exciplex at the interface as evident by photoluminescence spectrum.
We analyzed the effect of the change in device structure on the device efficiency in order to achieve the best efficiency with optimized charge balance. The optimized exciplex device without dopants showed external quantum efficiency of 12%, while the device doped with red fluorescent material showed external quantum efficiency of 9.2%. In addition, the device exhibited lifetime (T75) of 310 minutes with initial brightness of 1000 nits. Transient photoluminescence and transient electroluminescence measurement were carried out to analyze the exciplex mechanism.
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