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Updated: May 22, 2025
Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
Homochiral carbon nanotube van der Waals crystals
Zhichun Zhang1, Yi Chen1, Peiyue Shen1
1Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy and Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai, China.
Abstract:
For applications of single-walled carbon nanotubes (SWNTs) in integrated circuits, it is crucial to have high-tube density arrays of SWNTs that are well aligned and purely semiconducting. In this work, we report on the direct growth of close-packed SWNT arrays on hexagonal boron nitride (hBN) substrates, demonstrating high alignment and uniform chirality within each array. Molecular dynamics simulations suggest that a self-assembly growth mechanism resulted from the intertube van der Waals attraction and the ultralow sliding friction of SWNTs on the atomically flat hBN substrate. Field-effect transistors constructed from the grown SWNT array exhibit high performance at room temperature, with mobilities of up to 2000 square centimeters per volt per second, on/off ratios of ~107, and a maximum current density of ~6 milliamperes per micrometer.
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