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arXiv · 1704.04352

High mobility dry-transferred CVD bilayer graphene

Michael Schmitz·Stephan Engels·Luca Banszerus·Kenji Watanabe·Takashi Taniguchi·Christoph Stampfer·Bernd Beschoten
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Abstract

We report on the fabrication and characterization of high-quality chemical vapor-deposited (CVD) bilayer graphene (BLG). In particular, we demonstrate that CVD-grown BLG can mechanically be detached from the copper foil by an hexagonal boron nitride (hBN) crystal after oxidation of the copper-to-BLG interface. Confocal Raman spectroscopy reveals an AB-stacking order of the BLG crystals and a high structural quality. From transport measurements on fully encapsulated hBN/BLG/hBN Hall bar devices we extract charge carrier mobilities up to 180,000 cm$^2$/(Vs) at 2 K and up to 40,000 cm$^2$/(Vs) at 300 K, outperforming state-of-the-art CVD bilayer graphene devices. Moreover, we show an on-off ration of more than 10,000 and a band gap opening with values of up to 15 meV for a displacement field of 0.2 V/nm in such CVD grown BLG.

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Michael Schmitz, Stephan Engels, Luca Banszerus, Kenji Watanabe, Takashi Taniguchi, Christoph Stampfer, Bernd Beschoten. 2017-04-14. High mobility dry-transferred CVD bilayer graphene. https://doi.org/10.1063/1.4990390

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