All Solution-Processed Polymer Light-Emitting Diodes

Polymer light-emitting diodes (PLEDs) have great potential toward next generation light source because of their flexibility, facile fabrication, and simple structure. However, the fabrication of low-cost PLEDs is still quite challenging, owing to the vulnerability of cathode and electron injection/transportation materials against the oxygen and moisture in the air. In this paper, we propose an all solution-processable polymer light-emitting diode structure and lamination method. Generally, electrode layers are formed by vacuum deposition; however, in this study, a solution-processed Ag film was developed and used as an electrode. The solution-processed Ag film was transferred to a polymer hot-melt film and then laminated onto the PLED layer. The laminated device exhibited good performances in turn-on voltage (5.0 V), brightness (2500 cd/m²) and current efficiency (0.6 cd/A), which were comparable to that of the evaporated device.