Green Photolithography of Perovskite Nanocrystals: In Situ Silica Encapsulation for Stable Micro‐LED Displays

ABSTRACT Photolithographic patterning of perovskite nanocrystals (PeNCs) is pivotal for realizing color‐conversion schemes in full‐color Micro‐LED displays; however, this process is currently hindered by severe material degradation and a pervasive reliance on toxic organic solvents. Herein, we propose a robust PeNC photoresist strategy designed for compatibility with eco‐friendly green solvents, specifically enabling the use of benign ethanol as a developer for high‐resolution patterning. By synthesizing PeNCs directly within isobornyl acrylate (IBOA) monomers and engineering an in situ SiO 2 encapsulation layer via hydrolysis, we achieve superior material stability. Remarkably, the resulting PeNC@SiO 2 /IBOA composites retain bright fluorescence after 3480 h of ethanol immersion, whereas uncoated controls quench completely within 96 h. Leveraging this stability, we successfully patterned color conversion pixels with dimensions of 20 µm × 10 µm via photolithography with green solvent ethanol as the developer, which retain 80.3% of their initial photoluminescence quantum yield (PLQY) post‐lithography. The successful fabrication of highly uniform red, green, and blue (RGB) pixel arrays demonstrates the significant potential of this green, high‐performance lithography strategy of PeNCs for next‐generation Micro‐LED displays.