Highly Efficient Fine-Pitch Quantum Dot/Titanium Oxide Nanocomposites for Ultrahigh-Resolution Full-Color Micro-Light Emitting Diode Displays

The development of full-color micro-LED displays has driven research on color conversion technology. Although various color conversion methods have been proposed, practical fine-pitch displays have posed a challenge owing to the insufficient efficiency and low absorption in the slim thickness of color conversion material patterns and the serious optical crosstalk between adjacent subpixels. Herein, we introduce a prototype of a full-color micro-LED display featuring high-resolution colloidal quantum dot (QD)/TiO2 nanoparticle composite arrays with an active-matrix blue light micro-LED module. This innovative QD composite is prepared using a hybrid method involving ligand-selective dispersion and scattering particles, allowing a considerable increase in pattern resolution and conversion efficiency. Moreover, an optical structure design featuring a distributed Bragg reflector and a dual-site light-confining matrix is employed, resulting in a high color gamut of 92.8% with regard to the National Television Standards Committee. Finally, a 0.7 in. active-matrix QD micro-LED display prototype is demonstrated with a resolution of 960 × 540 (1588 ppi) for the first time.