Top-emitting organic light-emitting diodes (TOLEDs) employing highly reflective Ag as anode and semitransparent as cathode were fabricated. The hole injection efficiency of Ag anode can be significantly improved with surface modification using a plasma. With C545T-doped emitter, the top-emitting device shows a low turn-on voltage of . The optimized microcavity TOLED shows a current efficiency enhancement of 65% and a total outcoupling efficiency enhancement of 35%, compared with a conventional OLED. No color variation was observed in the forward 140° forward viewing cone. Strong dependence of efficiency on Ag cathode thickness was observed, in good agreement with numerical simulations.
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