Ultrasensitive UV-C detection based on MOCVD-grown highly crystalline ultrawide bandgap orthorhombic κ-Ga2O3

Orthorhombic κ-Ga2O3, as one of the Ga2O3 polymorphs, is considered a promising ultrawide bandgap material for extreme environment devices. It more superior than conventional group III-V compound semiconductors and silicon carbides in environments demanding material/device characteristics high-voltage, high-temperature, high-pressure, high-impact, high-radiation. In this study, we demonstrate ultrasensitive ultraviolet-C (UV-C) detection using Si-doped orthorhombic κ-Ga2O3 photodetectors. A 150 nm thick film was grown on 2-inch diameter sapphire (α–Al2O3) wafer via metal organic chemical vapor deposition (MOCVD) method. The crystallinity investigated by X-ray diffraction (XRD) transmission electron microscopy (TEM). approximately 4.9 eV confirmed UV transmittance measurement. For UV-C analysis, planar device with channel length 20 μm fabricated Au/Ti contacts film. doped under 15 sccm SiH4 flow rate showed ultrahigh photoresponse ∼72.1 A/W, Ion/Ioff ∼14, decent rise (∼0.35 s) decay (∼1.79 s). Our results will contribute to understanding new phase well developing optoelectronics devices high radiation hardness suitable operation environments.