An efficient flexible top-emitting organic light-emitting diode (FTOLED) was developed on a thin steel foil. The FTOLED was constructed on the spin-on-glass (SOG)-coated steel substrate with an organic stack of NPB/Alq(3) sandwiched by a highly reflective Ag anode and a semitransparent Sm cathode. An ultrathin plasma-polymerized hydrocarbon film (CFX) was interposed between the Ag anode and the NPB layer to enhance hole-injection, and an additional Alq(3) layer was overlaid on the Sm cathode to increase light output. The FTOLED showed a peak efficiency of 4.4 cd/A higher than 3.7 cd/A of a convention NPB/Alq(3)-based bottom-emitting OLED. (C) 2003 Elsevier B.V. All rights reserved.