Research on Deep-UV Photodetectors Based on Carbon Dots as Reactive Layer

Deep-ultraviolet (DUV) photodetectors are attracting attention due to their important applications in various fields. In this paper, carbon dots are used as an active layer to fabricate DUV photodetectors. These devices are capable of detecting UV light at wavelengths below 320 nm. Carbon dots are prepared by electrochemical method using distilled water as the electrolyte and their properties were characterized. A planar photoconductive structure is designed using carbon dots as reactive layer to prepare effective device by processes such as thermal evaporation and the performance of the device was estimated. The results show that the absorption peak of the carbon dots prepared by the electrochemical method is around 230 nm. A photodetector fabricated with carbon dots as an active layer has a good response at 254 nm illumination and the ratio of photocurrent to dark current of the device reaches 188.