Ultrafine-pitch AlGaN Ultraviolet-C microLED Displays for Quantum Dots Color Conversion

Aluminum Gallium Nitride (AlGaN) ultraviolet-C (UV-C) microlight-emitting diodes (microLEDs) offer significant advantages in terms of convenience, cost-effectiveness, and environmental friendliness, positioning them as promising candidates for display applications. However, achieving the desired high efficiency and scalability for large displays with ultra-fine pixels necessitates substantial progress beyond current experimental outcomes. This study showcases the application of AlGaN UV-C microLED display panels and micro-displays incorporating quantum dots (QDs) for color conversion. Sidewall treatment and atomic layer deposited (ALD) passivation effectively address dangling bonds and etching damages, leading to a notable enhancement of TMpolarized light extraction efficiency (LEE). Moreover, dedicated strain modulation efforts successfully reduce the high Al content (over 50%) wafer bowling effect, facilitating the modularization of ultrafine-pitch AlGaN UV-C microLED panels. Consequently, the devices achieve a peak performance of over 5% external quantum efficiency (EQE) as the mesa size scales down to 3 μm. The highlighted 0.18-inch UV-C microLED display panels, featuring a 9 μm pixel size, are precisely controlled by a CMOS IC driver to achieve desired patterns. Serving as an efficient pumping source for perovskite quantum dots paper (PQDP), this UV-C microLED display suggests the potential to revolutionize the full-color display industry by providing an innovative and unconventional solution. © 2024, John Wiley and Sons Inc. All rights reserved.