Sub-100 nm Channel ZnSe Film/Graphene Hybrid-Based Photodetectors With an Ultrahigh Responsivity of 109 A/W

Sub-100-nm channel length ZnSe film/ graphene hybrid-based photodetectors have been achieved using ZnS nanowire with an average diameter of 100 nm. The as-fabricated 70 nm-channel ZnSe film/graphene hybrid photodetector shows a fast response speed of 50 ms and an ultrahigh responsivity of 1.2 × 10
⁹
A/W, which is three orders of magnitude higher than that of 5 μm channel ZnSe film/graphene photodetector. Obviously, the channel length has a huge impact on the responsivity enhancement as the channel length decreases from micron scale to sub-100-nm scale.