Fig. 1. (Color online) (a) XRD ω−2θ scan and (b) FWHM of rocking curve for β-Ga₂O₃ films grown at different T_B. Inset shows the XRD ω scan for films.

Fig. 2. (Color online) (a) AFM images and (b) RMS roughness of β-Ga₂O₃ films, (c) film thicknesses obtained from the cross-sectional SEM. Inset shows the cross-sectional image of film grown at T_B = 700 °C.

Fig. 3. (Color online) (a) The optical microscope diagram and (b) structural diagram of MSM photodetector. (c) The I−V characteristics of the MSM photodetector in the dark and illuminated by 254 and 365 nm. (d) The energy band diagram and photogenerated carriers of MSM β-Ga₂O₃ detector with external bias under 254 nm illumination.

Fig. 4. (Color online) (a) The time-dependent photoresponse of the Ga₂O₃ photodetector with external bias to 254 nm illumination, (b) the experimental data and the fitting curve of rise and decay process.

Fig. 5. (Color online) (a) The photocurrent spectrum of β-Ga₂O₃ MSM detector at −1 V bias in semilog scale, (b) the responsivity vs detectivity of different solar-blind photodetectors^[32−41].