High Aspect Ratio Reflective Metallic Barriers for High‐Efficiency Quantum‐Dot Color Conversion in Micro‐LED Displays

Quantum dot color conversion (QDCC) is a promising route for next‐generation micro displays, offering exceptional emission tunability, high color purity, and seamless integration with blue micro‐LEDs. However, current QDCC technologies suffer from limited luminance and power efficiency due to severe optical losses from highly absorptive pixel‐defining barriers. Here, we report a QDCC architecture featuring high‐aspect‐ratio metallic barriers that can simultaneously suppress optical crosstalk and recycle otherwise wasted photons emitted from a blue micro‐LED. The metallic barriers were in the form of metal‐mesh which were made by scalable and cost‐effective imprinting, copper electroplating, and silver coating processes. The metal‐mesh barriers enabled a record resolution of 2540 pixels per inch (PPI), an aperture ratio >60%, a barrier height of ∼10 µm. The smooth and high‐aspect‐ratio sidewalls significantly enhanced optical confinement and achieved reflectance approaching 80%, which is the highest resolution of reflective barrier reported to date. The optical measurements revealed a greater than fourfold increase in QD emission because of the enhanced color conversion, confirming substantially improved photon confinement and energy‐conversion efficiency. This approach establishes a scalable route toward high‐efficiency full color Micro‐LED displays, paving the way for next‐generation augmented and virtual reality systems.