Efficient p-i-n Top-emitting Flexible Organic Light Emitting Diodes on Planarized Stainless Steel Foil

Abstract

A high-efficiency p-i-n top-emitting flexible organic light emitting diode (TFOLED) employing highly reflective Ag as anode and semitransparent Ca/Ag as cathode was fabricated on SS substrate which was insulated and planarized with a specially formulated photoresist coating. By incorporating p-dopant (WO(3)) and a new n-dopant (PAK2) in hole and electron transparent layers, respectively, along with an optimized microcavity structure, a green fluorescent C545T doped Alq(3) TOLED on SS substrate achieved one of the highest efficiencies of 26.7 cd/A and 19.8 lm/W at 20 mA/cm(2) reported for flexible OLEDs.