Figure 1
From: Ultrahigh-Gain Photodetectors Based on Atomically Thin Graphene-MoS2 Heterostructures
Spectroscopic characterizations of a graphene/MoS2 bilayer.
(a) Photo showing that a MoS2 monolayer was grown on the right hand side of the 300 nm SiO2/Si wafer followed by transferring graphene onto the bottom half. (b) Schematic illustration of the photodetector based on graphene/MoS2 stacked layers, where the channel is formed in between the comb-shaped source and drain metal electrodes (Ti/Au = 5 nm/80 nm). (c) A high-resolution TEM (HRTEM) image clearly reveals a bilayer stacking of graphene/MoS2. The thickness of each layer can be extracted from the intensity profile to be 0.36 nm and 0.7 nm for graphene and MoS2, respectively. (d) Raman spectra and (e) photoluminescence spectra for MoS2 and MoS2 covered by CVD monolayer graphene taken from the sample shown in (a). Note that the Raman intensity of Graphene/MoS2 in (d) has been multiplied by a factor of 10 for better comparison.
