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Dielectrophoretic Assembly of High-Density Arrays of Individual Graphene Devices for Rapid Screening

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 نشر من قبل Aravind Vijayaraghavan
 تاريخ النشر 2009
  مجال البحث فيزياء
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We establish the use of dielectrophoresis for the directed parallel assembly of individual flakes and nanoribbons of few-layer graphene into electronic devices. This is a bottom-up approach where source and drain electrodes are prefabricated and the flakes are deposited from a solution using an alternating electric field applied between the electrodes. These devices are characterized by scanning electron microscopy, atomic force microscopy, Raman spectroscopy and electron transport measurements. They are shown to be electrically active and their current carrying capacity and subsequent failure mechanism is revealed. Akin to carbon nanotubes, we show that the dielectrophoretic deposition is self-limiting to one flake per device and is scalable to ultra-large-scale integration densities, thereby enabling the rapid screening of a large number of devices.



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