Optimizing Zr Self-Compensation Doping Effect for High-Performance Wearable Amorphous Ga₂O₃ Photodetectors with Enhanced Durability in Harsh Environments

Flexible photodetectors have garnered significant attention in recent years due to their vast potential. Among these, amorphous Ga₂O₃ (a-Ga₂O₃) stands out as a highly promising candidate for flexible solar-blind ultraviolet photodetectors, owing to its wide band gap, low-temperature fabrication advantages, and exceptional stability under extreme conditions. However, the fabrication of a-Ga₂O₃ inevitably introduces oxygen vacancy (V_O) defects, leading to declined photodetection performance and compromised corrosion resistance. In this study, we developed a zirconium (Zr) self-compensation doping strategy with concentration optimization to suppress V_O defects, thus enhancing the optoelectronic performance and durability of flexible a-Ga₂O₃ photodetectors. The introduction of Zr significantly eliminated intrinsic V_O defects in Ga₂O₃ films, lowering the dark current by over 3 orders of magnitude from ∼10^-8 to ∼10^-11 A and reducing the response time by a factor of 50, achieving a response time of 6 μs. The detectivity of the optimized devices reached a high level of 3 × 10¹⁴ Jones, indicating exceptional sensitivity to ultraviolet light. Durability tests further demonstrated that the optimized devices exhibited outstanding mechanical robustness, maintaining over 95% of their initial performance after 10,000 bending cycles, and stable photodetection performance even under harsh salt spray conditions for 72 h. This work provides an effective solution for developing high-performance flexible photodetectors tailored for wearable devices and applications in harsh environments.