SID DW2020 58.4: Providing a research platform for QLEDs

OPERA Solutions is capable of fabricating several types of QLED samples for evaluation. To provide our customers with reliable data, we often utilize the inverted structure.

Cadmium selenide-based quantum dots are the current standard for QD applications, which are, however, subject to the RoHS restriction. Non-toxic cadmium-free QD materials, such as indium phosphide-based QDs, are highly anticipated by industry. We propose a novel approach for an efficient cadmium-free QLEDs by inserting a thin assist layer between the exciton blocking layer and the QD emitting layer.

The TADF assist layer plays a role as an exciton energy reservoir, and the excitons are eventually transferred to the QD layer by means of Foerster resonance energy transfer, resulting in a sharp red emission. We believe that in the near future, by utilizing suitable energy reservoir materials, highly efficient red and green cadmium-free QLEDs will be available, which will also pave the way for a stable cadmium-free blue QLED.

For more details, please see the YouTube video.