α-Ga2O3 Photodetector with Responsivity over A/W Level Based on Sn-Assisted Mist-CVD

In recent years, α-Ga
₂
O
₃
and α-Ga
₂
O
₃
-based photodetectors have garnered significant attention due to their unique advantages in deep-ultraviolet photodetection. However, the growth of α-Ga
₂
O
₃
thin films via the mist-CVD method faces several challenges, such as inferior crystallization quality, which impedes the development of high-performance photodetectors. In this study, we successfully achieved high-quality α-Ga
₂
O
₃
epitaxy on the α-Al
₂
O
₃
substrate using the Sn-assisted mist-CVD technique. A deep-ultraviolet photodetector was subsequently fabricated on the epitaxial film, and its detection performance was thoroughly evaluated. The photodetector achieved a photocurrent of up to 175.40 nA and a signal-to-noise ratio of 76.5 dB. Most notably, it also exhibited a high responsivity of up to 3.76 A/W, an external quantum efficiency of 1841.12% and a detectivity of 1.8×10
¹¹
Jones, underscoring the potential of the Sn-assisted mist-CVD method for advancing the development of next-generation α-Ga
₂
O
₃
deep-ultraviolet photodetectors.