As　Micro-LED　sizes　shrink,　luminescence　efficiency　drops　significantly　due　to　sidewall　damage　from　plasma　etching.　This　study　introduces　a　precision-selective　ion　implantation　(PSII)　strategy　to　boost　external　quantum　efficiency　(EQE)　and　brightness　of　Micro-LED　at　high　current　density,　vital　for　applications　like　augmented　reality　(AR)　and　optical　communication,　instead　of　relying　on　sidewall　passivation　for　low　current　density　efficiency.　PSII＇s　effects　is　systematically　evaluated　on　electrical　isolation　and　photoelectric　properties.　Results　demonstrate　that　Micro/Nano-LED　arrays　with　a　pixel　density　up　to　25,400　ppi　are　achieved　through　the　PSII　strategy.　Turn-off　leakage　current　is　reduced,　with　improved　carrier　injection　efficiency,　EQE,　and　luminance.　At　10,000　A　cm-　2,　EQE　and　brightness　increased　by　approximate　to　30%　and　approximate　to　25%,　respectively.　Moreover,　lattice　damage　induced　by　ion　bombardment　enhanced　UV　and　blue　light　absorption　while　suppressing　visible　emission,　which　benefits　photodetectors　(PDs).　Demonstrations　in　AR　displays,　optical　communication　systems,　and　UV　PDs　showed　superior　performance　compared　to　etching-based　methods.　The　modulation　bandwidth　reached　131.2　MHz,　a　30%　improvement,　and　PD　photocurrent　increased　by　approximate　to　90%.　This　PSII-based　pixelation　strategy　enables　high-brightness　Micro-LED　displays　with　significant　potential　for　multifunctional　integrated　applications,　offering　a　robust　alternative　to　traditional　etching　processes　for　advanced　optoelectronic　devices.