연사: 송  명  훈  교수님 (울산과학기술대)

일시: 2012년 6월 13(수) 오후4:30

장소: 제1과학관 31214  e+첨단강의실

초록: We investigate the dipole effect on ZnO surface in hybrid organic-inorganic polymeric light-emitting diodes (HyPLEDs). Despite the dipole layer between ZnO surface and active layer being extremely thin, the magnitude and orientation of dipole moment effectively influenced the work function of the ZnO. As a consequence, the charge injection barrier between the conduction band of the ZnO and the lowest unoccupied molecular orbital of poly(9,9’-dioctylfluorene)-co-benzothiadiazole (F8BT) could be efficiently controlled resulting that electron injection efficiency is remarkably enhanced. The HyPLEDs modified with a negative dipolar layer exhibited enhanced device performances, which correspond to approximately a fourfold compared to those of unmodified HyPLEDs.