Design and fabrication of patterned high performance quantum-dot color conversion films for μLED full color display applications

The fabrication and performance of patterned quantum dot color conversion films are of great significance for μLED full color displays. In this work, TiO2 nanoparticles was designed and introduced to mix with quantum dots (QDs) as well as photoresist polymer to prepare the patterned quantum-dot photoresist (QDPR) films using direct photolithography, and to improve the color conversion efficiency (CCE) of QDPR. The results show that uniform QDPR films with controllable thickness and size could be achieved by optimizing the photolithography process parameters, whose minimum dimension can reach 12 μm. And the maximum CCE of patterned QDPR films was up to 67.46% with the thickness of only 4.28 μm. In addition, distributed Bragg reflector (DBR) and black matrix (BM) were employed to regulate the outgoing light and reduce the optical crosstalk, respectively. A color conversion device using a blue μLED and the QDPR films incorporated with DBR and BM have been demonstrated, with the color gamut of 120.53% NTSC, exhibiting the potential application for the next-generation high resolution full-color displays.