In Situ Fabrication of Vertical Multilayered MoS2/Si Homotype Heterojunction for High-Speed Visible-Near-Infrared Photodetectors

摘要

C2D transition metal dichalcogenides (TMDCs)-based heterostructures have been demonstrated to achieve superior light absorption and photovoltaic effects theoretically and experimentally, making them extremely attractive for realizing optoelectronic devices. In this work, a vertical multilayered n-MoS2-silicon homotype heterojunction is fabricated, which takes advantage of multilayered MoS2 grown in situ directly on plane silicon. Electrical characterization reveals that the resultant device exhibits high sensitivity to visible-near-infrared light with responsivity up to 11.9 A W-1. Notably, the photodetector shows high-speed response time of approximate to 30.5 mu s/71.6 mu s and capability to work under higher pulsed light irradiation approaching 100 kHz. The high response speed could be attributed to a good quality of the multilayer MoS2, as well as in situ device fabrication process. These findings suggest that the multilayered MoS2/Si homotype heterojunction have great potential application in the field of visible-near-infrared detection and might be used as elements for construction of high-speed integrated optoelectronic sensor circuitry.