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arXiv · 2005.01920

Twisted bilayer graphene fabricated by direct bonding in a high vacuum

Hitoshi Imamura·Anton Visikovskiy·Ryosuke Uotani·Takashi Kajiwara·Hiroshi Ando·Takushi Iimori·Kota Iwata·Toshio Miyamachi·Kan Nakatsuji·Kazuhiko Mase·Tetsuroh Shirasawa·Fumio Komori·Satoru Tanaka
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Abstract

Twisted bilayer graphene (TBG), in which two monolayer graphene are stacked with an in-plane rotation angle, has recently become a hot topic due to unique electronic structures. TBG is normally produced in air by the tear-and-stack method of mechanical exfoliation and transferring graphene flakes, by which a sizable, millimeter-order area, and importantly clean interface between layers are hard to obtain. In this study, we resolved these problems by directly transferring the easy-to-exfoliate CVD-grown graphene on SiC substrate to graphene in a high vacuum without using any transfer assisting medium and observed electronic band modulations due to the strong interlayer coupling.

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Hitoshi Imamura, Anton Visikovskiy, Ryosuke Uotani, Takashi Kajiwara, Hiroshi Ando, Takushi Iimori, Kota Iwata, Toshio Miyamachi, Kan Nakatsuji, Kazuhiko Mase, Tetsuroh Shirasawa, Fumio Komori, Satoru Tanaka. 2020-05-09. Twisted bilayer graphene fabricated by direct bonding in a high vacuum. https://doi.org/10.35848/1882-0786%2Fab99d1

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