Investigation of WO3-doped Ga2O3 films as Deep-ultraviolet and Visible-light Photodetectors

WO 3 -doped Ga 2 O 3 films, deep-ultraviolet, visible-light, photodetectors, interdigital electrode Deep-ultraviolet (DUV) and visible-light photodetectors have attracted considerable attention owing to their important applications in environmental monitoring, optical communication, image sensing, and intelligent sensing systems.However, most reported photodetectors are optimized for either the DUV or visible-light region, making broadband photodetection over 250-430 nm difficult.In this study, WO 3 -doped Ga 2 O 3 films were deposited on Si substrates by a simple electron-beam (E-beam) evaporation process, and interdigital aluminum electrodes were fabricated to construct broadband photodetectors.SEM observations revealed dense and uniform films with a thickness of approximately 131 nm, while energy dispersive spectrometry confirmed the successful incorporation of W into the Ga 2 O 3 matrix.X-ray diffraction (XRD) analysis showed that the deposited films were amorphous, whereas UV-visible spectroscopy indicated a wide optical bandgap of 4.66 eV.The fabricated photodetectors exhibited characteristic photoresponse peaks at 250, 280, 360, and 430 nm and demonstrated stable current-voltage characteristics, excellent repeatability during five consecutive ON/OFF cycles, and stable response times over the wavelength range of 280-430 nm.The objective of this work is to investigate whether a simply fabricated WO 3 -doped Ga 2 O 3 thin-film photodetector can provide measurable photoresponse extending from the DUV toward the visible-light region.