Electroluminescence(EL) devices with poly(
p-phenylene vinylene) (PPV) as light emitting layer (ITO/PPV/Mg) and LiClO
4 doped PPV as emitting layer (ITO/LiClO
4 doped PPV/Mg) were fabricated. In the ITO/PPV/Mg EL device, the EL intensity increased as the thermal conversion temperature of PPV precursor to PPV decreased from 260 ℃ to 140 ℃. In the ITO/LiClO
4 doped PPV/Mg EL device, the threshold voltage for light emission decreased to above 5 volt compared to about 8 volt of ITO/PPV/Mg EL device. The ITO/PVK/PPV/Mg EL device in whice hole transport/electron blocking PVK layer was inserted between ITO and PPV layer showed higher EL intensity and longer life than ITO/PPV/Mg EL device.
발광층으로 poly(p-phenylene vinylene) (PPV)를 사용하여 ITO/PPV/Mg 단층구조의 EL 소자와 PPY 발광층에 LiClO
4가 도핑된 ITO/LiClO
4 doped PPV/Mg EL 소자를 제작하였다. 단층구조의 EL 소자에서 PPY의 열변환 온도가 260 ℃에서 140 ℃로 낮아질수록 발광 휘도가 증가하였으며 LiC1O
4를 도핑하면 문턱 발광전압이 감소되었다. 또 hole transport/electron blocking성질을 가지는 poly(vinyl carbazole) (PVK) 층이 도입된 ITO/PVK/PPV/Mg 이층구조이 EL 소자에 있어서는 ITO/PPV/Mg 단층구조 EL 소자보다 발광 휘도 및 안정성~이 증가됨이 관찰되었다.
Keywords: electroluminescene devices (ELD); organic ELD; polymer ELD; doping of PPV; stability of EL device