Au-modified ZnO thin films for higher-performance ultraviolet photodetectors.

ABSTRACT: ZnO-based ultraviolet (UV) photodetectors are widely studied due to their wide bandgap and higher photosensitivity. However, the ZnO thin-film UV photodetectors face higher dark current and limited gain despite their wide bandgap advantage. Here, Au overlayers (5-40 nm) were deposited on optimized 221 nm ZnO (prepared via sol-gel method) films using cost-effective spin-coating (ZnO film) and RF sputtering (Au overlayers). Au induces Schottky barriers (ϕ _Au = 5.47 eV > ϕ _ZnO = 4.45 eV) that suppress dark current down to 7.29 nA. Meanwhile, plasmonic Au nanoparticles generate localized surface plasmon resonance (LSPR) hot electrons that enhance UV absorption and photocurrent. The device with a 10 nm Au overlayer achieves an excellent photoresponse o

SUBMITTER: Rajan A 

PROVIDER: S-EPMC12703354 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature