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arXiv · 1702.05726

Solving the graphene electronics conundrum: high mobility and high on-off ratio in graphene nanopatterned transistors

Mircea Dragoman·Adrian Dinescu·Daniela Dragoman
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Abstract

Tens of graphene transistors with nanoperforated channels and different channel lengths were fabricated at the wafer scale. The nanoholes have a central diameter of 20 nm and a period of 100 nm, the lengths of the channel being of 1, 2, 4 or 8 micrometers. We have found that the mobility in these 2 micrometer-wide transistors varies from about 10400 cm2/Vs for a channel length of 1 micrometer to about 550 cm2/Vs for a channel length of 8 micrometer. Irrespective of the mobility value, in all transistors the on-off ratio is in the range 10^3-10^4 at drain and gate voltages less than 2 V. The channel length-dependent mobility and conductance values indicate the onset of strong localization of charge carriers, whereas the high on-off ratio is due to bandgap opening by nanoperforations.

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Mircea Dragoman, Adrian Dinescu, Daniela Dragoman. 2017-02-19. Solving the graphene electronics conundrum: high mobility and high on-off ratio in graphene nanopatterned transistors. https://doi.org/10.1016/j.physe.2017.12.011

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