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

摘要

Abstract: The thermal elimination conditions for more efficient poly(p- phenylene vinylene) polymer light-emitting diodes were established: the precursor films must be heated to 230 degrees Celsius and kept at that temperature for 5 min. under a N$-2$/ flow of 50 ml/min. By the heat treatment the degree of conversion to PPV was about 70%. The external quantum efficiency of 0.0078% was achieved for the ITO/70% PPV/Al devices. The brightness of the device was calculated from the efficiency to be 2.3 cd/m$+2$/ at 200 MV/m (current density of 0.2 mA/mm$+2$/). !17