Fig. 1. (Color online) Design of the UV sensitive element based on the α-Ga₂O₃ film.

Fig. 2. (Color online) (a) XRD spectrum of the Ga₂O₃ film grown on the c-plane sapphire. (b) Cross-sectional SEM image of the α-Ga₂O₃ film on Al₂O₃. (c) Dependence of α² on photon energy.

Fig. 3. (Color online) I−V curves of the UVC detectors based on the HVPE grown α-Ga₂O₃ films in dark conditions and under the exposure to irradiation at λ = 254 nm and P = 620 µW/cm².

Fig. 4. (Color online) Spectral dependencies of photo to dark current ratio (a), responsivity (b), detectivity (c), and external quantum efficiency (d) of the UVC detectors at V = 1 V.

Fig. 5. (Color online) Dependencies of the photo to dark current ratio (a), responsivity (b), detectivity (c), and external quantum efficiency (d) of the UVC detectors on applied voltage at λ = 254 nm and P = 620 µW/cm².

Fig. 6. (Color online) Time dependencies of the normalized total current through the UV detector based on the HVPE grown α-Ga₂O₃ film at cyclic exposure (a), (b) and single exposure (c), (d) to irradiation at λ = 254 nm, P = 620 µW/cm² and different operation modes.

Fig. 7. (Color online) Schematic representation of the different operation modes of SBUVDs based on HVPE grown α-Ga₂O₃ film with Pt contacts, where E_c is the condition band bottom; E_v is the valence band top.