Growth Optimization of Bridging Ga₂O₃ Nanowires and the Effect of Oxygen on their Optoelectronic Properties

Ga 2 O 3 is regarded as a promising wide‐bandgap (4.9 eV) semiconductor for solar‐blind photodetectors (SBPDs). Ga 2 O 3 nanowires (NWs) demonstrate a low dislocation density and strong photogenerated carrier separation effect owing to their high surface‐to‐volume ratio, rendering them suitable for high‐performance SBPDs. However, NW devices often face challenges such as complex fabrication and unstable metal–electrode contacts. In this study, Ga 2 O 3 NWs are in situ integrated by bridging growth through chemical vapor deposition. The light‐sensitive NW–NW junctions in the bridging NWs effectively suppress dark current. By adjusting the growth time and electrode spacing, the number of NW–NW junctions could be regulated to optimize photoelectric performance, achieving a high light–dark current ratio (4.09 × 10 3 ), high detectivity (7.46 × 10 12 Jones), and relatively fast response and recovery times (0.050 and 0.175 s). Moreover, the effect of the oxygen atmosphere ratio on bridging growth and optoelectronic properties is investigated. Increasing the oxygen ratio hinders the growth of NWs and widens their bandgaps, whereas a lower oxygen ratio generates excessive oxygen vacancies, which weakens the NW–NW junction effect. Establishing this relationship between the oxygen atmosphere ratio and optoelectronic properties provides insights into the optoelectronic mechanism of Ga 2 O 3 NWs.