Imaging Ultra-weak UV Light Below 100 pW/cm² Using a 4H-SiC Photodetector with an Al2O3 Interfacial Layer

Weak light detection is crucial in various practical applications such as night vision systems, flame monitoring, and underwater operations. Decreasing the dark current of a photodetector can effectively mitigate noises, consequently enhancing the signal-to-noise ratio and overall weak light detection performance. Herein, we demonstrate a 4H-SiC UV photodetector capable of detecting extremely weak UV light. This device comprises a photosensitive layer of 4H-SiC, two TiN electrodes and an atomically thin Al