Van der Waals heterostructures have attracted increasing interest, owing to the combined benefits of their constituents. These hybrid nanostructures can be realized via epitaxial growth, which offers a promising approach for the controlled synthesis of the desired crystal phase and the interface between van der Waals layers. Here, the epitaxial growth of a continuous molybdenum disulfide (MoS2) film on large-area graphene, which was directly grown on a sapphire substrate, is reported. Interestingly, the grain size of MoS2 grown on graphene increases, whereas that of MoS2 grown on SiO2 decreases with an increasing amount of hydrogen in the chemical vapor deposition reactor. In addition, to achieve the same quality, MoS2 grown on graphene requires a much lower growth temperature (400 °C) than that grown on SiO2 (580 °C). The MoS2/graphene heterostructure that was epitaxially grown on a transparent platform was investigated to explore its photosensing properties and was found to exhibit inverse photoresponse with highly uniform photoresponsivity in the photodetector pixels fabricated across a full wafer. The MoS2/graphene heterostructure exhibited ultrahigh photoresponsivity (4.3 × 104 A W−1) upon exposure to visible light of a wide range of wavelengths, confirming the growth of a high-quality MoS2/graphene heterostructure with a clean interface.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) funded by the Korean government (MSIT) (NRF-2015R1A3A2066337) and the European Union’s Horizon 2020 research and innovation program under grant agreement 881603-GrapheneCore3. Ken Teo of AIXTRON Ltd. is gratefully acknowledged for support in the wafer-scale growth of graphene on sapphire.
All Science Journal Classification (ASJC) codes
- Materials Science(all)