Nanowires mediated growth of β-Ga₂O₃ nanobelts for high-temperature (> 573 K) solar-blind photodetectors

β-Ga₂O₃, with ultra-wide bandgap, high absorption coefficient for high-energy ultraviolet (UV) photons, and high structural stability toward harsh-environment, has been receiving persistent attention for deep ultraviolet photodetectors applications. However, realization of devices with high tolerance toward high temperature faces great challenges due to considerable background signals mainly arising from abundant thermal excited carrier. Herein, nanowire-mediated high-quality β-Ga₂O₃ nanobelts with ultra-thin thickness and length up to several hundred micrometers were achieved via a simple catalyst-free chemical vapor deposition route. The resulted microdevice output superior optoelectric figure of merits among numerous reports about β-Ga₂O₃, i.e., ultra-low dark current (below the detection limit of 10⁻¹² A), high responsivity (1,320 A/W), and high spectral selectivity working under low voltage (~ 2 V). More importantly, the performance remains robust at elevated temperature higher than 573 K. These results indicate a large prospect for low-voltage driven deep ultraviolet photodetectors with good sensitivity and stability at harsh environments.