Thin Film Encapsulation of Light-Emitting Diodes with Photopolymerized Polyacrylate and Silver Films

A thin film encapsulation of organic light-emitting diodes (OLEDs) is investigated with a multi-layer stack of polyacrylate-Ag-polyacrylate-Ag-polyacrylate-Ag-polyacrylate (PAPAPAP). It is shown that the fabrication of polyacrylate films by a wet process does not affect the electroluminescent (EL) characteristics of the devices and polyacrylate films together with the silver layers can perform to minimize oxygen and water diffusion into the organic light-emitting device. The structure of polyacrylate(20μm)-Ag(200nm) polyacrylate(20μm)-Ag(200nm)-polyacrylate(20μm)-Ag(200nm)-polyacrylate(20μm) is demonstrated to enhance dramatically the lifetime of OLEDs.