Fig. 1. Schematic diagram of the photodetector fabrication^[15]

Fig. 2. Fabrication of high-quality ZnO crystal microrod arrays and their morphological characterization. (a) The silicon micropillar template with lyophobic sidewalls and lyophilic tops. (b) The sandwich-type assembling system composed of the GaN substrate, precursor solution, and micropillar template. (c) The dewetting process of the continuous liquid layer and the formation of capillary bridges. (d) Precursor ZnO crystal arrays on the GaN substrate. (e) Precursor ZnO arrays with a coated TiO₂ thin film as the mask. (f) As-fabricated high-quality ZnO crystal microrod arrays on the GaN substrate. SEM images of ZnO microrod arrays with different diameters of (g–h) 2.2 µm and (i–j) 1.3 µm, respectively. (k–n) Topographical images of ZnO microrod arrays corresponding to (g–j) obtained by the laser scanning confocal microscopy. (All scale bars, 1 µm)^[16].

Fig. 3. (a) The optical image of a flexible ZnO MW/polyaniline photodetector on a PET substrate. (b) I-t curve of the flexible ZnO MW/polyaniline photodetector under 365 nm UV switching (3mW/cm²) at −1 V bias with various bending angles. (c) I-t curve of the flexible ZnO MW/polyaniline photodetector under 365 nm UV switching (3 mW/cm²) at −1 V bias after bending cycles^[32]

Fig. 4. Schematic diagram of the fabrication of vertical Schottky photodiode of β-Ga₂O₃ nanowires array film ^[54]

Fig. 5. Structural diagram of Ga₂O₃ NRAs PEC photodetectors^[67]