Atomic layer deposition (ALD) offers a low thermal budget method for producing α-Ga2O3 films on sapphire substrate. The related paper reviews the recent progress on plasma-enhanced ALD growth of α-Ga2O3 and present
the optical and photoconductive properties of the deposited films. The structure of the samples was investigated by X-ray diffraction (XRD) using a PANalytical Empyrean diffractometer with a Cu Kα1 X-ray source. A two-bounce Ge analyser was used for 2θ-ω scans, and a PIXcel detector was used to acquire reciprocal space maps. The atomic structure of the samples was observed using highangle annular dark-field scanning transmission electron microscopy (HAADF-STEM) in an aberration-corrected FEI Titan operated at 200 kV.23 The optical bandgap of the material was obtained using a Shimadzu UV-2600 UV-vis transmittance spectrophotometer equipped with an integrating sphere. The luminescence properties were obtained using room temperature cathodoluminescence (CL) in a JEOL JXA-8530F field-emission electron probe microanalyser (EPMA) operated at 5 kV. Finally, photoelectric characterisation was performed using a Signatone
probe station equipped with a Thorlabs Deuterium light source coupled to a SolarLS ML44 monochromator to illuminate the sample with a monochromatic light.