Ultrahigh-resolution quantum-dot light-emitting diodes

The demonstration of high-resolution quantum-dot light-emitting diodes by transfer printing could prove useful for next-generation displays. With the ever-growing demand for a greater number of pixels, next-generation displays have challenging requirements for resolution as well as colour gamut. Here, to meet this need, quantum-dot light-emitting diodes (QLEDs) with an ultrahigh pixel resolution of 9,072-25,400 pixels per inch are realized via transfer printing combined with the Langmuir-Blodgett film technology. To reduce the leakage current of the devices, a honeycomb-patterned layer of wide-bandgap quantum dots is embedded between the light-emitting quantum-dot pixels as a non-emitting charge barrier layer. Red and green QLEDs are demonstrated. Notably, the red devices achieve a brightness of up to 262,400 cd m(-2) at an applied voltage of 8 V and a peak external quantum efficiency of 14.72%. This work provides a promising way for achieving ultrahigh-resolution QLED devices with high performance.

Automated summary

The demonstration of high-resolution quantum-dot light-emitting diodes using transfer printing and Langmuir-Blodgett film technology has been achieved. A honeycomb-patterned layer of wide-bandgap quantum dots is embedded to reduce leakage current, and both red and green QLEDs are demonstrated. The red devices exhibit high brightness and peak external quantum efficiency.