Utilizing novel hybrid color conversion thin film for ultra-high resolution and thin micro-LED arrays

Micro-LED is a highly anticipated next-generation display technology, recognized for its high brightness and resolution, making it a promising candidate for future applications in the augmented reality field. The color conversion technique utilized in this study for Micro-LED fabrication addresses issues related to time-consuming mass transfer and the challenge of achieving smaller pixel sizes (5 μm). Unlike other color conversion materials, such as quantum dots and perovskites, the novel hybrid color conversion material we employed is free of rare earth elements and other harmful substances, while also exhibiting high environmental stability. When the array thickness is reduced to 2 μm, the optimal color conversion efficiency (CE) for green light is achieved by doping with 25 wt % TiO₂ particles sized at 170 nm, reaching a CE of 74.2 %. For red light, the optimal CE is achieved by doping with 25 wt % TiO₂ particles sized at 240 nm, with a CE of 62.1 %. The fabrication process involves photolithography, which quickly patterns the spin-coated film, followed by etching to create the array. The high-resolution monochromatic conversion array density is 11548 PPI, and the full-color conversion array density is 5774 PPI. Each array pixel size is 1.4 μm, and it boosts a wide color gamut with a DCI-P3 gamut ratio of 149.73 % and a gamut coverage of 96.98 %.