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Red-emitting fluorescent Organic Light emitting Diodes with low sensitivity to self-quenching S.Forget(1)*, S.Chenais(1), D.Tondelier(2), B.Geffroy(2), I.Gozhyk(3), M.Lebental(3), and E.Ishow(4) (1) Laboratoire de Physique des Lasers, Université Paris 13 / CNRS UMR 7538, Villetaneuse, France (2) Laboratoire de Physique des Interfaces et Couches Minces, Ecole Polytechnique, CNRS UMR 7647, Palaiseau, France (3) Laboratoire de Photonique Quantique et Moléculaire, ENS Cachan, CNRS UMR 8537, France (4) Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires, ENS Cachan, CNRS UMR 8531, France *E-mail : sebastien.forget@univ-paris13.fr Keywords: OLED, quenching, doping, red-emitting organic material Abstract Concentration quenching is a major impediment to efficient organic light-emitting devices. We herein report on Organic Light-Emitting Diodes (OLEDs) based on a fluorescent amorphous red-emitting starbust triarylamine molecule (4-di(4’-tert-butylbiphenyl-4-yl)amino- 4’-dicyanovinylbenzene, named FVIN), exhibiting a very small sensitivity to concentration quenching. OLEDs are fabricated with various doping levels of FVIN into Alq3, and show a remarkably stable external quantum efficiency of 1.5% for doping rates ranging from 5% up to 40%, which strongly relaxes the technological constraints on the doping accuracy. An efficiency of 1% is obtained for a pure undoped active region, along with deep red emission (x=0.6; y=0.35 CIE coordinates). A comparison of FVIN with the archetypal DCM dye is presented in an identical multilayer OLED structure. 1. Introduction Organic Light Emitting Diodes (OLEDs) have proven their potential as efficient and low-cost sources for lighting and flat panel displays1,2. Their efficiency strongly depends on the properties of the organic materials used for each layer of the OLED architecture, including light-emitting and charge carri