Three-color polymer light-emitting diodes by stamped dye diffusion

Abstract

A method to pattern the integrated emissive colors of polymer light-emitting diodes (PLEDs) using stamped dye diffusion is introduced. In this method, the emitting colors are tuned selectively by the energy transfer processes from the host polymer to the diffused dye. The diffusion of the dye into the emitting polymer layer was successfully achieved by transferring the prefabricated dye pattern onto a silicon substrate at an elevated temperature. Coumarin6, 4-(dicyanomethylene)2-methyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran and Nile Red dyes were diffused selectively into a poly (9-vinylcarbazole)-based emitting layer using this method. We have investigated the electroluminescent properties of the dye diffused PLEDs and also have demonstrated the integration of three-color PLEDs with dimensions of the order of 10 μm.