A Review on Quantum Dot‐Based Color Conversion Layers for Mini/Micro‐LED Displays: Packaging, Light Management, and Pixelation

Abstract

Mini/microlight‐emitting diodes (LEDs) are one of the most promising technologies for next‐generation displays to meet the requirements of demanding applications, including augmented reality/virtual reality displays, wearable devices, and microprojectors. To realize full‐color displays, the strategy of combining miniaturized blue nitride‐based LEDs with color conversion layers is promising due to the high efficiencies of the LEDs and the advantageous manufacturing. Quantum dots (QDs), owing to their high photoluminescence quantum yield, small particle size, and solution processability, have emerged as the color conversion material with the most potential for mini/micro‐LEDs. However, the integration of QDs into display technologies poses several challenges. From the material side, the stability of QD materials is still challenging. For the case of packaging QDs in a matrix, the dispersion quality of QDs and the light extraction of the emission need to be improved. From the fabrication side, the lack of high‐precision mass manufacturing strategies in QD pixelation hinders the widespread application of QDs. Toward the issues above, this review summarizes the research on QD materials for color conversion display in recent years to systematically draw an overview of the packaging strategies, the light management approaches, and the pixelation methods of QD materials toward mini/micro‐LED‐based display technologies.

A Photoinitiator-Grafted Photoresist for Direct In Situ Lithography of Perovskite Quantum Dots

“…Colloidal quantum dots (QDs) have emerged as an excellent engineering material for next generation optoelectronic and photonic devices due to their fascinating color persistence, exceptional color purity, and excellent photoluminescence quantum yield (PLQY). − In particular, QDs have evolved as powerful light-emitting materials in various displays including light-emitting diode (LED), − color converted OLED, and Micro-LED. − Recently, there has been increasing interest in the utilization of QDs in next-generation displays such as augmented reality glasses, which provide contents that is both vivid and realistic . To integrate QDs into these realistic displays, the QD layer should be uniformly patterned into red-green-blue (RGB) full-color pixel arrays on a scale of a few microns or less .…”

Organosilicon-Based Ligand Design for High-Performance Perovskite Nanocrystal Films for Color Conversion and X-ray Imaging

“…All-inorganic CsPbX 3 (X = Cl, Br, or I) perovskite nanocrystals (PNCs) have attracted tremendous interest owing to their broadly tunable photoluminescence (PL) across 400–700 nm, narrow PL full-width at half-maximum (fwhm), and high PL quantum yield (PLQY). − Given these appealing features, CsPbX3 NCs demonstrate great potential, especially for applications in optics and photonics, including light-emitting diodes (LEDs), − displays, , lasers, , single-photon source, , and X-ray scintillators. − Furthermore, the relatively low formation energy and the high defect tolerance of the lead-halide PNCs enable the preparation of highly fluorescent materials at low temperatures and low cost, hence greatly broadening its application prospects . However, the labile surface and metastable ionic structure of PNCs cause poor stability against heat, moisture, and UV radiation. − For example, surface decomposition and increased trap state densities of CsPbX 3 PNCs are observed under oxygen-rich and humid conditions .…”

Magnetic circuit optimisation and actuator suspension experiment of the 6‐DOF magnetic suspension platform for mini/micro LED

“…Mini/Micro LED is a novel display technology with applications in oversized displays, virtual reality (VR)/augmented reality (AR) displays, wearable displays, and various other display fields [1]. The primary challenge hindering the large‐scale application of Mini/Micro LED displays is the manufacturing speed, commonly referred to as mass transfer speed [2].…”