P‐114: White and Top‐Emitting Quantum‐Dot Light‐Emitting Diodes with Indium‐Tin‐Oxide Top Electrodes

Abstract

Top-emitting white quantum-dot light-emitting diodes (QLEDs) have great promise for the active-matrix display applications because the light emitting from the top electrodes greatly increases the aperture ratio of the display, while by working with color filters, they could enable the realization of high resolution, large area and full color display. However, it is difficult to achieve white emission in a conventional top-emitting structure due to the microcavity effect. In this work, we develop white and top-emitting QLEDs by using indium-tin-oxide (ITO) as the top electrodes, which greatly alleviate the undesired microcavity effect. To enhance hole injection from bottom Al anode to the TFB hole transport layer, the double hole injection layers MoO3/PEDOT:PSS are utilized, and to protect the quantum dots (QDs) from damaging by the plasma, a compact electron transport layer based on ZnMgO:PVP composite is used. As a consequence, the demonstrated devices exhibit a high brightness of 12980 cd m -2 , a pure white color with a 1931 Commission International de I'Eclairage (CIE) coordinate of (0.33, 0.33) and a high color stability. The demonstrated white and top-emitting QLEDs, with high brightness and high color stability, would be ideal candidates for next generation active-matrix display and solid-state lighting applications.