Flexible top-emitting electroluminescent devices on polyethylene terephthalate substrates

An aluminum-laminated polyethylene terephthalate (Al-PET) is used as the substrate for flexible organic light-emitting devices (OLEDs). The efficient flexible electroluminescent devices have a top-emitting OLED architecture. An acrylic layer is formed on the Al-PET surface to improve the surface morphology and also the adhesion between the substrate and the anode. Poly(styrene sulfonate)-doped poly(3,4-ethylene dioxythiophene) was used as hole transporting layer. The light-emitting polymer used is a phenyl-substituted poly($p$ -phenylenevinylene). Bilayer anodes of $\mathrm{Ag}∕\mathrm{C}{\mathrm{F}}_X$ and Ag/indium-tin oxide and a semitransparent top cathode were used for the flexible polymer OLEDs. For a flexible polymer OLED with a $110\text{-}\mathrm{nm}$ -thick light-emitting polymer, it exhibited superior electrical and optical characteristics with a luminous efficiency of $4.56\mathrm{cd}∕\mathrm{A}$ at an operating voltage of $7.5\mathrm{V}$ .