Solving efficiency-stability tradeoff in top-emitting organic light-emitting devices by employing periodically corrugated metallic cathode.

The introduction of a periodic corrugation into TOLEDs is demonstrated to be effective in relieving the tradeoff between device stability and efficiency, through the cross coupling of the SPPs associated with the Ag cathode and the microcavity modes. The thickness of the Ag cathode for the corrugated TOLEDs was increased from 20 to 45 nm, and both the device lifetime and efficiency are significantly improved. The figure shows a schematic cross section of a red TOLED with periodic microstructure and an operating TOLED with both corrugated and planar area.