Wakafuji Yusai, Moriya Rai, Masubuchi Satoru, Watanabe Kenji, Taniguchi Takashi, Machida Tomoki
Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo 153-8505, Japan.
National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan.
Nano Lett. 2020 Apr 8;20(4):2486-2492. doi: 10.1021/acs.nanolett.9b05228. Epub 2020 Mar 17.
We demonstrate 3D mechanical manipulations, such as sliding, rotating, folding, flipping, and exfoliating, of 2D materials using a microdome polymer (MDP) via in situ real-time observation with an optical microscope. A dimethylpolysiloxane (PDMS)-based MDP is covered with a poly(vinyl chloride) (PVC) adhesion layer. This PVC-MDP structure enables us to achieve small and adjustable contact areas between the PVC-MDP and a 2D-material flake, which is typically between ∼10 and ∼100 μm in diameter. The adhesion between the PVC polymer and 2D materials is fully tunable with temperature: Strong adhesion at ∼70 °C allows pick-up of the 2D material, and release occurs at ∼130 °C when the adhesion is weak. Thus the PVC-MDP functions as a point-of-contact manipulator for 2D materials, permitting the 3D manipulation of 2D-material flakes. Our method could facilitate the expansion of van der Waals heterostructure fabrication technology and the development of preparation techniques for more complex 3D structures.
我们通过光学显微镜进行原位实时观察，展示了使用微穹顶聚合物（MDP）对二维材料进行的三维机械操作，如滑动、旋转、折叠、翻转和剥落。基于聚二甲基硅氧烷（PDMS）的MDP覆盖有聚氯乙烯（PVC）粘附层。这种PVC-MDP结构使我们能够在PVC-MDP和二维材料薄片之间实现小且可调节的接触面积，二维材料薄片的直径通常在10到100微米之间。PVC聚合物与二维材料之间的粘附力可随温度完全调节：在约70°C时具有强粘附力，可拾取二维材料，而在约130°C时粘附力较弱时则会释放。因此，PVC-MDP充当二维材料的接触点操纵器，允许对二维材料薄片进行三维操作。我们的方法可以促进范德华异质结构制造技术的扩展以及更复杂三维结构制备技术的发展。
