Lithography-Assisted Assembly of Single-Layer Gold Nanoparticle Micropatterns for Plasmonic Biosensor Applications

We present a lithography-assisted assembly of the patterns of single-layer gold nanoparticles (AuNPs) for fabrication of plasmonic biosensors and devices. A digital UV lithography technology is employed to pattern nanometer-thin acrylic resin at the micrometer scale. Citrate-stabilized AuNPs are then applied to assemble a single layer of AuNPs on the surface of patterned acrylic resin via a self-assembly process. The refractive index sensing ability of such a micropatterned AuNPs was experimentally demonstrated to reveal the potential of the proposed technology in the fabrication of plasmonic biosensors. Such a lithography-assisted assembly technology bridges the facile chemical synthesis and maskless UV lithography at the nanometer and micrometer levels, respectively, and thus may offer a versatile pathway to fabricate complex plasmonic structures and devices for micro/nano-photonic and biotechnological applications.