Fig. 1. Schematic structure of the β-Ga₂O₃/LCMO pn junction APD.

Fig. 2. (a) XRD patterns of β-Ga₂O₃/LCMO/STO (red line) and LCMO/STO (black line); (b) atomic diagram of cross section in the (100) direction of pn junction.

Fig. 3. Solar-blind photoresponse characteristics of Ga₂O₃/LCMO APD. (a) I-V curves (log scale) in dark and under different light illumination (1–100 µW/cm²). The inset shows the I-V curves enlarged near −37 V. (b) Reverse I-V curves in dark and under 1 µW/cm² 254 nm light intensity; the right axis shows the multiplication gain values. (c) The light intensity-dependent photocurrent and responsivity at a reverse bias of 20 V. (d) Photoresponse spectrum at a reverse bias of 30 V.

Fig. 4. (a) Responsivity; (b) EQE; and (c) LDR of Ga₂O₃/LCMO pn junction APD under 1 µW/cm² 254 nm UV light intensity as a function of reverse bias.

Fig. 5. CL and valence band XPS energy spectrum of (a) LCMO (∼100 nm)/STO and (b) Ga₂O₃ (∼300 nm)/LCMO (∼100 nm)/STO; (c) CL XPS energy spectrum of Ga₂O₃ (∼3 nm)/LCMO (∼100 nm)/STO sample; (d) bandgap of Ga₂O₃ film; and (e) LCMO film determined by Tauc plots method; (f) band alignment at the Ga₂O₃/LCMO pn junction.

Fig. 6. Avalanche multiplication process of Ga₂O₃/LCMO APD.