Fig. 1. (a) SEM image of Ga2O3 microwires. (b) EDS mapping image of Au. (c) XRD patterns of β-Ga2O3 microwires grown at 1100°C. (d) Raman spectrum of β-Ga2O3 microwires.

Fig. 2. (a) Schematic illustration of the Ga2O3/WSe2 JFET. (b) Optical microscopy image of the Ga2O3/WSe2 JFET. (c) EDS mapping images of the Ga, O, W, and Se elements. AFM measurement of the thickness of (d) WSe2 and (e) Ga2O3. (f) KPFM image at the Ga2O3/WSe2 interface. (g) SPD plot of the measured Ga2O3/WSe2 interface. Energy band of the Ga2O3/WSe2 heterojunction (h) before and (i) after contact.

Fig. 3. (a) Ids−Vds curves at Vg=0  V under dark conditions. (b) Temporal response of the device for 635 nm illumination at Vg=−5  V and 5 V. (c), (d) Time-dependent photocurrent of the Ga2O3/WSe2 JFET under light illumination at 635 nm at Vds=1  V and Vg=5  V (−5  V) in response to different laser power. (e) Time-dependent photoresponse under 100 on/off switching cycles. (f) A single modulation cycle at Vds=1  V and Vg=5  V under 635 nm illumination for estimating both the rise and fall times.

Fig. 4. (a) Output curves at different gate voltages of the JFET under 635 nm illumination with a power intensity of 194.52  mW/cm2. (b) Photocurrent and detectivity as a function of different gate voltages at Vds=1  V. (c) Responsivity and external quantum efficiency of JFET under different gate voltages. (d) Output curves at Vg=5  V of the JFET under different laser powers. (e) Photocurrent and detectivity as a function of different laser powers at Vds=1  V. (f) Responsivity and external quantum efficiency of JFET under different laser powers at Vds=1  V.

Fig. 5. (a) Ids−Vg curves under dark conditions and 635 nm illumination. (b) Igs−Vg curves under dark conditions and 635 nm illumination. (c)–(f) Energy band diagrams at the heterojunction with 635 nm illumination at different Vg. (g) Schematic illustration of the depletion region at Vg=−5  V and (h) Vg=5  V. (i) Fowler-Nordheim plots of current of the Ga2O3/WSe2 heterojunction device.

Fig. 6. (a) Schematic diagram of the Ga2O3/WSe2 JFET under 635 nm illumination. (b) Schematic illustration of NAND logic gate. (c) Truth table corresponding to Ga2O3/WSe2 JFET. (d) Realized logic function with respect to the input of Vg and light. (e) Schematic diagram of the binary code translation based on the Ga2O3/WSe2 JFET.