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Measurement of specific contact resistivity using scanning voltage probes

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 نشر من قبل Weigang Wang
 تاريخ النشر 2012
  مجال البحث فيزياء
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Specific contact resistivity measurements have conventionally been heavy in both fabrication and simulation/calculation in order to account for complicated geometries and other effects such as parasitic resistance. We propose a simpler geometry to deliver current, and the use of a scanning voltage probe to sense the potential variation along the sample surface, from which the specific contact resistivity can be straightforwardly deduced. We demonstrate an analytical example in the case where both materials are thin films. Experimental data with a scanning Kelvin probe measurement on graphene from the literature corroborates our model calculation.

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