Temperature-Dependent Study of β-Ga₂O₃ Solar-Blind Photodetectors

In this paper, the electrical and ultraviolet optoelectronic properties of the interdigitated finger geometry β-Ga2O3 photodetector were investigated from the temperature of 40 K to 300 K. Under different light illumination conditions, when the temperature increased from 40 K to 300 K, the maximum current of the β-Ga2O3 photodetector was obtained around 180 K, which is related to the carrier mobility of β-Ga2O3. Under 365-nm illumination, when the temperature increased from 40 K to 300 K, the photo-to-dark current ratio (PDCR) of the β-Ga2O3 photodetector increased by 924%. Under 254-nm illumination, the PDCR decreased by 87%. Besides, the temperature point corresponding to the photoresponse peak under 365-nm illumination moved to the right under 254-nm illumination, indicating that the photodetector had a redshift at low temperature. Moreover, the fast photoresponse time under 365-nm and 254-nm illumination decreased when the temperature increased. This indicated that the defect concentration of Ga2O3 decreased gradually as the temperature increased, leading to the faster response time of the photodetector.