| 초록 |
N,N-bis(4-(tert-butyl)phenyl)-3,5-bis(3,6-di-tert-butyl-9H-carbazol-9-yl)aniline (t-DCDPA), which is modified from 3,5-di(9H-carbazol-9-yl)-N,N-diphenylaniline (DCDPA) by substituting t-butyl group, was synthesized. DCDPA and t-DCDPA successfully formed Exciplex with 2,8-bis(4,6-diphenyl-1,3,5-triazin-2-yl)dibenzo[b,d]furan (DBFTrz). DCDPA:DBFTrz exicplex pair showed 2.95 eV of triplet energy and t-DCDPA:DBFTrz exciplex pair showed 2.94 eV of triplet energy, which can cover energy of deep-blue phosphorescent emitter. In device, DCDPA:DBFTrz pair and t-DCDPA:DBFTrz pair were used as an exciplex host. To compare ability of exciplex hosts, unipolar host devices also were fabricated. As a result, exciplex host device showed better performance than unipolar host system, and t-DCDPA:DBFTrz device showed the highest external quantum efficiency (16.4%). This experiment demonstrated that modified hole type material is more effective in deep-blue phosphorescent OLED than the other one. |
