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Thickness-Dependence Electrical Characterization of the One-Dimensional van der Waals TaSe₃ Crystal.

ABSTRACT: Needle-like single crystalline wires of TaSe₃ were massively synthesized using the chemical vapor transport method. Since the wedged-shaped single TaSe₃ molecular chains were stacked along the b-axis by weak van der Waals interactions, a few layers of TaSe₃ flakes could be easily isolated using a typical mechanical exfoliation method. The exfoliated TaSe₃ flakes had an anisotropic planar structure, and the number of layers could be controlled by a repeated peeling process until a monolayer of TaSe₃ nanoribbon was obtained. Through atomic force and scanning Kelvin probe microscope analyses, it was found that the variation in the work function with the thickness of the TaSe₃ flakes was due to the interlayer screening effect. We believe that our results will not only help to add a novel quasi-1D block for nanoelectronics devices based on 2D van der Waals heterostructures, but also provide crucial information for designing proper contacts in device architecture.

SUBMITTER: Kim BJ

PROVIDER: S-EPMC6695938 | biostudies-literature |

REPOSITORIES: biostudies-literature

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