Fiber‐Inspired Quantum‐Dot Micropillar Pixel Architecture for Micro‐LED Displays

ABSTRACT Quantum‐dot (QD) color conversion pixels with partitioned black matrix (BM) enable low‐crosstalk color generation for Micro‐LED displays, yet conventional structures face an inherent trade‐off, the crosstalk‐suppressing BM induces parasitic absorption and reduces conversion efficiency. Inspired by the light‐confining core‐shell structure of optical fibers, we propose a novel reflective QD micropillar pixel architecture for high‐efficiency, crosstalk‐suppressed full‐color Micro‐LED displays. Vertically aligned QD micropillar pixel array is fabricated via in situ photolithography, followed by sidewall deposition of a highly reflective aluminum (Al) cladding layer via evaporation. Unlike conventional planar color conversion layers, where the optical path is inherently constrained by film thickness, the vertically aligned three‐dimensional (3D) micropillar fundamentally extends the interaction length between excitation light and QDs. By further enabling metal‐mirror multiple reflections of excitation light within the micropillar, this design substantially prolongs the optical path and fosters secondary excitation, leading to a marked improvement in color conversion efficiency (CCE). Furthermore, the Al cladding forms a lateral photon‐recycling microcavity, mitigating BM absorption and optical crosstalk. Breaking the efficiency and crosstalk trade‐off, our device achieves green CCE of 27.15%, red CCE of 28.6%, and an ultra‐wide color gamut of 131.54% NTSC, promising for near‐eye full‐color Micro‐LED light engines.