Prepatration of light-emitting divices with poly(p-phenylenevinylene) : effects of thermal elimination conditions and polymer layer thickness on device performance

초록

The thermal elimination conditions for more efficient poly (p-phenylene vinylene) polymer light-emitting diodes were established:the precursor films must be heated to 230oC and kept at that temperature for 5min. under a N2 flow of 50ml/min. By the heat treatment the degree of conversion to PPV was about 70%. THe external quantum efficiency of 0.007% was achieved for the ITO/70% PPV/Al devices. The brightness of the device was calculated from the efficiency to be 2.2cd/m2 at 200 MV/m(current density of 0.2mA/mm2).