Architectural float glass as a substrate for organic light-emitting diodes

While ITO has proven a succesful transparent anode material for laboratory-based investigations of OLEDs, it is perhaps less suited to large-scale production. Here we show that float glass with an evaporated gold coating functions extremely well as the transparent anode for OLEDs. We discuss the production of an ultrathin conductive gold layer in terms of the roughness and surface energy of the float glass. We demonstrate large area OLEDs based on these substrates, in particular a green-emitting device using spin-coated films of Poly[(9,9-dioctylfluorenylene-2,7-diyl)-co-(1,4-diphenylene-vinylene-2-methoxy-5-{2-ethylhexyloxy}-benzene)] as the active layer, and a white-emitting device using, as the active layer, spin-coated films of Poly(9-vinylcarbazole) doped with the phosphorescent materials Iridium bis(2-(4,6-difluorophenyl)pyridinato-N,C2′)picolinate and Iridium bis(2-(2′-benzothienyl)pyridinato-N, C3′)(acetylacetonate). Atomic force microscopy was used to investigate the morphology during each stage of OLED fabrication. We show that large area OLEDs can be fabricated on such substrates, with the area limited by the deposition techniques used.