Radiation effects in β -Ga2O3-based devices: From atomic-scale damage to radiation hardening strategies

β-Ga2O3, with its ultrawide bandgap and high critical electric field, has emerged as a candidate material of interest for space power electronics and solar-blind ultraviolet photodetectors. Its theoretical breakdown field far exceeds that of SiC and GaN, positioning it as a promising candidate for high-voltage, high-efficiency power devices. However, prolonged exposure to protons, neutrons, heavy ions, and γ-rays in the space radiation environment can induce single-event effects, displacement damage, and total ionizing dose effects, leading to gradual performance degradation or even catastrophic failure. Thus, understanding the physical origins of radiation damage, systematically elucidating the evolution of device failure, and developing effective radiation-hardening strategies have become central challenges in the field. This review focuses on the interplay between defects and charge carriers as a core mechanism, starting from the anisotropy of displacement threshold energies and the dynamics of collision cascades to establish a physical link between key defects and device performance degradation. It provides an in-depth analysis of the synergistic effects of electric-field concentration and thermal accumulation in single-event burnout, the modulation of carrier lifetime by deep-level defects in displacement damage, and the coupled influence of bias conditions and temperature on interface degradation under total ionizing dose. Based on these insights, this review summarizes radiation-hardening technologies, including deep trench structures, phase engineering, and electrical scanning recovery, thereby establishing a comprehensive framework that bridges fundamental physics with practical engineering solutions for the reliable design of Ga2O3-based devices in aerospace and nuclear applications.