High-Performance Harsh-Environment-Resistant GaOX Solar-Blind Photodetectors via Defect and Doping Engineering

Gallium oxide (Ga2O3), with an ultrawide bandgap, is currently regarded as one of the most promising materials for solar-blind photodetectors (SBPDs), which are greatly demanded in harsh environment, such as space exploration and flame prewarning. However, realization of high-performance SBPDs with high tolerance toward harsh environments based on low-cost Ga2O3 material faces great challenges. Here, defect and doping (DD) engineering towards amorphous GaOX (a-GaOX) has been proposed to obtain ultrasensitive SBPDs for harsh condition application. Serious oxygen deficiency and doping compensation of the engineered a-GaOX film ensure the high response currents and low dark currents, respectively. Annealing item in nitrogen of DD engineering also incurs the recrystallization of material, formation of nanopores by oxygen escape, and suppression of sub-bandgap defect states. As a result, the tailored GaOX SBPD based on DD engineering not only harvests a record-high responsivity rejection ratio (R-254 nm/R-365 nm) of 1.8 x 10(7), 10(2) times higher detectivity, and 2 x 10(2) times faster decay speed than the control device, but also keeps a high responsivity, high photo-to-dark current ratio, and sharp imaging capability even at high temperature (280 degrees C) or high bias (100 V). The proposed DD engineering provides an effective strategy towards highly harsh-environment-resistant GaOX SBPDs.

Automated summary

The study proposes a defect and doping engineering strategy towards amorphous GaOX (a-GaOX) to achieve highly tolerant and ultra-sensitive solar-blind photodetectors for harsh environments, maintaining high performance even under high temperature or high voltage conditions.