【Epitaxy Papers】Amorphous GaOx Thin Films Grown by MOCVD for Broadband Ultraviolet Absorption Application

      Researchers from the Hong Kong University of Science and Technology (Guangzhou) have published a dissertation titled "Amorphous GaOx Thin Films Grown by MOCVD for Broadband Ultraviolet Absorption Application" in Advanced Materials Technologies.

Abstract

      Gallium oxide (Ga₂O₃), with its wide bandgap of 4.3–5.4 eV and tunable properties, holds great potential for applications in power electronics, solar-blind photodetectors (PDs), and transparent conductive oxides, particularly effective in the 230–280 nm range for solar-blind detectors. In contrast, amorphous gallium oxide (a-GaOx) is gaining attention for UV PDs and flexible X-ray detectors due to its straightforward synthesis. However, its effective utilization requires a deeper understanding of its chemical, structural, and optical properties. In this study, a-GaOx is synthesized using metal–organic chemical vapor deposition (MOCVD) at a reduced oxygen flow rate. X-ray photoelectron spectroscopy revealed that Ga₂O can constitute over 30% of the thin film at high trimethylgallium (TMGa) flux, coexisting with Ga₂O₃ and exhibiting an optical bandgap ≈3.3 eV. Notably, a metal-semiconductor-metal photodetector fabricated from this a-GaOx thin film demonstrated potential as a novel broadband ultraviolet (BUV) absorption material, effectively covering the 254 to 360 nm range.

DOI：

https://doi.org/10.1002/admt.202401215