High‐performance silicon‐based PbSe-CQDs infrared photodetector

Silicon technology is dominant in electronics and optoelectronics. The cut-off wavelength of silicon is less than 1.1 m due to the bandgap, limiting applications of silicon in communication, sensing, and light harvesting. A new strategy for infrared photodetection is presented by integrating silicon and PbSe colloidal quantum dots (CQDs), which combines advantages of silicon devices and PbSe-CQDs. In this study, we introduce a silicon-based photodetector that is sensitive to infrared light with spectral response from 405 nm to 1550 nm. The device can deliver a high responsivity of 648.7AW − 1 and a fast response of 32.3 s at 1550 nm. Besides, the detectivity and the external quantum efficiency of the device reached 7.48 × 10 10 Jones and 6.47 × 10 4