CMOS-Compatible Tellurium/Silicon Ultra-Fast Near-Infrared Photodetector

High-quality photodetectors are always the main way to obtain external information, especially near-infrared sensors play an important role in remote sensing communication. However, due to the limitation of Silicon (Si) wide bandgap and the incompatibility of most near infrared photoelectric materials with traditional integrated circuits, the development of high performance and wide detection spectrum near infrared detectors suitable for miniaturization and integration is still facing many obstacles. Herein, the monolithic integration of large area tellurium optoelectronic functional units is realized by magnetron sputtering technology. Taking advantage of the type II heterojunction constructed by tellurium (Te) and silicon (Si), the photogenerated carriers are effectively separated, which prolongs the carrier lifetime and improves the photoresponse by several orders of magnitude. The tellurium/silicon (Te/Si) heterojunction photodetector demonstrates excellent detectivity and ultra-fast turn-on time. Importantly, an imaging array (20 x 20 pixels) based on the Te/Si heterojunction is demonstrated and high-contrast photoelectric imaging is realized. Because of the high contrast obtained by the Te/Si array, in comparison with the Si arrays, it significantly improve the efficiency and accuracy of the subsequent processing tasks when the electronic pictures are applied to artificial neural network (ANN) to simulate the artificial vision system.