High-sensitivity silicon: PbS quantum dot heterojunction near-infrared photodetector

The integration of silicon and infrared-sensitive materials to manufacture infrared detectors is very promising. However, the combination of silicon and colloidal quantum dots (CQDs) to form stable and high-quality junctions still has problems. In this work, Si: PbS CQD heterojunction near-infrared photodetector was fabricated. The experimental results show that the PbS CQDs extend the detection band of Si substrate to the near-infrared. What's more, when the bias voltage is 0.05 V at room temperature, the responsivity of the device at 1064 nm and 1310 nm are 0.68 A/W and 0.29 A/W respectively. The specific detection is 7.74 × 1010 Jones for 1064 nm and 3.32 × 1010 Jones for 1310 nm. This research is expected to promote the development of related silicon-based near-infrared photodetectors.