Large-area synthesis and transfer of multilayer hexagonal boron nitride for enhanced graphene device arrays

• Published in: Nature electronics Vol. 6; no. 2; pp. 126 - 136
• Main Authors: Fukamachi, Satoru, Solís-Fernández, Pablo, Kawahara, Kenji, Tanaka, Daichi, Otake, Toru, Lin, Yung-Chang, Suenaga, Kazu, Ago, Hiroki
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06-02-2023
• Subjects: 639/166/987; 639/301/1005/1007; 639/925/357/1018; 639/925/918/1052; Electrical Engineering; Engineering
• ISSN: 2520-1131; 2520-1131
• DOI: 10.1038/s41928-022-00911-x

Multilayer hexagonal boron nitride (hBN) can be used to preserve the intrinsic physical properties of other two-dimensional materials in device structures. However, integrating the material into large-scale two-dimensional heterostructures remains challenging due to the difficulties in synthesizing high-quality large-area multilayer hBN and combining it with other two-dimensional material layers of the same scale. Here we show that centimetre-scale multilayer hBN can be synthesized on iron–nickel alloy foil by chemical vapour deposition, and then used as a substrate and as a surface-protecting layer in graphene field-effect transistors. We also develop an integrated electrochemical transfer and thermal treatment method that allows us to create high-performance graphene/hBN heterostacks. Arrays of graphene field-effect transistors fabricated by conventional and scalable methods show an enhancement in room-temperature carrier mobility when hBN is used as an insulating substrate, and a further increase—up to a value of 10,000 cm
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Multilayers of hexagonal boron nitride can be grown using a chemical vapour deposition process on iron–nickel foil and integrated into a large array of graphene devices that exhibit room-temperature carrier mobilities of up to around 10,000 cm
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