A HgTe/ZnO quantum dots vertically stacked heterojunction low dark current photodetector

Colloidal quantum dots（CQDs）are affected by the quantum confinement effect，which makes their bandgap tunable. This characteristic allows these materials to cover a broader infrared spectrum，providing a cost-effective alternative to traditional infrared detector technology. Recently，thanks to the solution processing properties of quantum dots and their ability to integrate with silicon-based readout circuits on a single chip，infrared detectors based on HgTe CQDs have shown great application prospects. However，facing the challenges of vertically stacked photovoltaic devices，such as barrier layer matching and film non-uniformity，most devices integrated with readout circuits still use a planar structure，which limits the efficiency of light absorption and the effective separation and collection of photo-generated carriers. Here，by synthesizing high-quality HgTe CQDs and precisely controlling the interface quality，we have successfully fabricated a photovoltaic detector based on HgTe and ZnO QDs. At a working temperature of 80 K，this detector achieved a low dark current of 5. 23×10^-9 A cm^-2，a high rectification ratio，and satisfactory detection sensitivity. This work paves a new way for the vertical integration of HgTe CQDs on silicon-based readout circuits，demonstrating their great potential in the field of high-performance infrared detection.