Photoluminescence intensity enhancement of nanorod micro-LEDs via localized surface plasmon coupling

Nano-light-emitting diodes (LEDs) are ideal for ultra-high resolution displays due to their small size and high pixel density. However, traditional photolithography techniques fall short in meeting the requirements for nanoscale LED fabrication. Besides, as the size decreases and the specific surface area increases, non-radiative recombination generated by sidewalls defects becomes a significant issue, affecting the efficiency of nano-LEDs. To address this challenge, a nano-LED array with a single nanorod size of 800 nm was fabricated in this work by using nanosphere lithography and etching technology. Meanwhile, localized surface plasmons (LSPs) coupling technology was employed to enhance the PL efficiency of these nano-LEDs. By comparing with bare nano-LEDs, the PL intensity was boosted by about 43% and 129% when Ag and Ag@SiO2 nanoparticles were added separately. The existence of LSPs coupling process has been further confirmed through time-resolved photoluminescence measurement and finite element simulation analysis of different samples. The results provide compelling evidence for the LSPs coupling technology in enhancing the efficiency of nanoscale LEDs.