Work

Emission Enhancement of ZnO Thin Films in Ultraviolet Wavelength Region Using Au Nano-Hemisphere on Al Mirror Structures

Year: 2025

Type: article

Abstract: Using a heterogeneous metal Nano Hemisphere on Mirror (NHoM) structure, composed of an Al2O3 thin film and Au nano-hemispheres formed on a thick Al film, we successfully generated two distinct surface plasmon resonance (SPR) peaks: one in the ultraviolet (UV) wavelength range below 400 nm and another in the visible range between 600 and 700 nm. This NHoM structure can be fabricated through a straightforward process involving deposition, sputtering, and annealing, enabling rapid, large-area formation. By adjusting the thickness of the Al2O3 spacer layer in the NHoM structure, we precisely controlled the localized surface plasmon resonance (LSPR) wavelength, spanning a wide range from the UV to the visible spectrum. Through this tuning, we enhanced the band-edge UV emission of the ZnO thin film by a factor of 35. Temperature-dependent measurements of emission intensity revealed that the NHoM structure increased the internal quantum efficiency (IQE) of the ZnO thin film from 8% to 19%. The heterometallic NHoM structure proposed in this study enables wide-ranging control of SPR wavelengths and demonstrates significant potential for applications in enhancing luminescence in the deep ultraviolet (DUV) region, where luminescence efficiency is typically low.

Source: Nanomaterials

DOI: 10.3390/nano15050400

Authors: Shogo Tokimori, Kai Funato, Kenji Wada, Tetsuya Matsuyama, Koichi Okamoto

Institution: Osaka Metropolitan University

Language: English

Topic: ZnO doping and properties

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,896

Funder: Japan Society for the Promotion of Science