Fig. 1. (Color online) (a) Experimental procedures of the Mist-CVD. (b) Fabrication process of the HJD−PD.

Fig. 2. (Color online) Optical absorbance spectra of (a) PEDOT:PSS film and (b) Sn:α-Ga₂O₃ film (the inset calculates the E_g of the Sn:α-Ga₂O₃ film). (c) XRD pattern of Sn:α-Ga₂O₃.

Fig. 3. (Color online) (a) Surface of the Sn:α-Ga₂O₃ thin film and (b) interface of Sn:α-Ga₂O₃ and PEDOT:PSS. (c) Cross-section SEM photograph at the interface of PEDOT:PSS and Sn:α-Ga₂O₃.

Fig. 4. (Color online) (a) The XPS spectrum of the sample of the Sn:α-Ga₂O₃ film. (b) The high-resolution XPS spectrum of the Ga 2p_1/2 and Ga 2p_3/2. (c) The high-resolution XPS spectrum of the O 1s. (d) The UPS spectrum of the Sn:α-Ga₂O₃ film.

Fig. 5. (Color online) Logarithmic coordinate I−V curve of (a) HJD (the inset is the linear coordinate I−V curve) and (b) Sn:α-Ga₂O₃ PD. (c) R, (d) EQE, (e) D*, and (f) the functional relationship between the I_ph and light intensity (the inset is the relationships at different devices and bias).

Fig. 6. (Color online) I−t curves of the HJD under different light intensities and different biases, (a) 0 V, (b) −5 V, and (c) 5 V. (d) I−t curves of the Sn:α-Ga₂O₃ PD under different light intensities and 5 V bias.

Fig. 7. (Color online) Fitted curve of the current rise and decay processes responding to 254 nm light of HJD under (a) 0 V, (b) −5 V, and (c) 5 V. (d) Sn:α-Ga₂O₃ PD under 5 V bias.

Fig. 8. (Color online) Schematic energy band diagrams of the PEDOT:PSS/Sn:α-Ga₂O₃ hybrid heterojunction under (a) before contact, (b) dark, and (c) ultraviolet illumination at 0 V bias.