深藍光應用於顯示器可提升全彩顯示器的色彩飽和度，使其具有更寬廣的色域，能顯示更真實的畫面，是製作高品質全彩顯示器不可或缺的元素之一；對於製作有機發光二極體(Organic Light Emitting Diode, OLED)技術來說，濕式製程適用於大面積之連續滾印，能大幅降低生產成本，故開發出一可濕式製作的深藍光染料極為重要；此外，深藍螢光材料相較於深藍磷光材料，其穩定性佳、合成容易且成本低，因此較能廣泛運用；本研究利用一新穎咔唑深藍螢光客體材料7,7'-((9,9-dibutyl-9H-fluorene-2,7-diyl)bis(ethyne-2,1-diyl))bis(9-(2-ethylhexyl)-9H-carbazole-2-carbonitrile) (JV55)，摻雜於3,3'-Di(9H-carbazol-9-yl)biphenyl (mCBP) 主體材料，並藉由濕式製程，研製出一高效率深藍光有機發光二極體；於摻雜濃度3wt%，其元件性能，在亮度100 cd/m2下，其能量效率為1.7 lm/W，外部量子效率為5.5％，CIE坐標為 (0.16, 0.06)；而最大外部量子效率可達6.5%及最大亮度為1,974 cd/m2；此外，利用此深藍光搭配美國國家電視標準委員會 (National Television System Committee, NTSC)所制定之標準紅綠光，色彩飽和度可達101%；此一元件之高效率，可歸因於(1) 良好的元件結構設計，有利於載子注入主體，並於主體上產生激子，以避免激子於客體產生，造成激子焠熄，降低效率；(2) 合適的主客體搭配下，可有效地將能量由主體傳遞給客體，進而提高元件效率；(3) 低主客體摻雜濃度，可避免焠熄效應所造成的效率滾降。

Deep-blue emission is crucial for achieving high-quality display, while solution processing enables organic devices, fabricated cost-effectively with a large area-size via continuous roll-to-roll manufacturing. Remarkably, deep-blue emission also broadens the color gamut and increase the color saturation of display to show more realistic image. We demonstrate here a highly efficient solution-processable deep-blue emitting diode by utilizing a novel carbazole-based fluorescent emitter 7,7'-((9,9-dibutyl-9H-fluorene-2,7-diyl)bis(ethyne-2,1-diyl))bis(9-(2-ethylhexyl)-9H-carbazole-2-carbonitrile) (JV55). The resultant device showed a maximum external quantum efficiency (EQE) of 6.5% and a power efficacy of 1.7 lm/W and EQE of 5.5% at 100 cd/m2 with CIE coordinates of (0.16, 0.06). Additionally, the deep-blue emission also realized a 101% color saturation according to the NTSC standard. The high efficiency may be attributed to engineering appropriate device architecture and enabling balanced carrier injection, effective host-to-guest energy transfer, and low doping concentration inhibiting efficiency roll-off due to concentration quenching.

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