A High-Performance ε-Ga₂O₃-Based Deep-Ultraviolet Photodetector Array for Solar-Blind Imaging.

Area of Science:

• Optoelectronics
• Materials Science
• Semiconductor Physics

Background:

• Photodetectors are crucial sensing units in imaging systems.
• High uniformity and performance in photodetector arrays are essential for practical imaging applications.
• Epsilon-gallium oxide (ε-Ga2O3) is a promising material for ultraviolet optoelectronic devices.

Purpose of the Study:

• To construct a photodetector array using ε-Ga2O3 thin films for solar-blind imaging.
• To investigate the performance characteristics of ε-Ga2O3-based photodetector units.
• To demonstrate a high-uniformity and high-performance solar-blind ultraviolet detector array.

Main Methods:

• Fabrication of a 5 × 4 photodetector array using low-cost magnetron sputtering and mask processes.
• Preprocessing of commercial ε-Ga2O3 films via high-temperature annealing for the photosensitive layer.
• Characterization of the photodetector units' responsivity, detectivity, light-to-dark ratio, and photoresponse speed.

Main Results:

• The ε-Ga2O3 ultraviolet photodetector unit achieved excellent responsivity (6.18 A/W) and detectivity (5 × 10^13 Jones).
• An ultra-high light-to-dark ratio of 1.45 × 10^5 and fast photoresponse speed (0.14/0.09 s) were observed.
• The fabricated array demonstrated good solar-blind characteristics, stability, high uniformity, and high performance.

Conclusions:

• A high-performance, uniform ε-Ga2O3 thin-film-based solar-blind ultraviolet detector array was successfully demonstrated.
• The developed array is suitable for solar-blind imaging in optoelectronic integration applications.
• The findings highlight the potential of ε-Ga2O3 for advanced UV detection systems.