Contact-free sheet resistance determination of large area graphene layers by an open dielectric loaded microwave cavity

Research output: Contribution to journalArticlepeer-review

Authors

  • O. Shaforost
  • K. Wang
  • S. Goniszewski
  • M. Adabi
  • Z. Guo
  • J. Gallop
  • L. Hao
  • N. Klein

Colleges, School and Institutes

External organisations

  • Imperial College London
  • National Physical Laboratory

Abstract

A method for contact-free determination of the sheet resistance of large-area and arbitrary shaped wafers or sheets coated with graphene and other (semi) conducting ultrathin layers is described, which is based on an open dielectric loaded microwave cavity. The sample under test is exposed to the evanescent resonant field outside the cavity. A comparison with a closed cavity configuration revealed that radiation losses have no significant influence of the experimental results. Moreover, the microwave sheet resistance results show good agreement with the dc conductivity determined by four-probe van der Pauw measurements on a set of CVD samples transferred on quartz. As an example of a practical application, correlations between the sheet resistance and deposition conditions for CVD graphene transferred on quartz wafers are described. Our method has a high potential as measurement standard for contact-free sheet resistance measurement and mapping of large area graphene samples.

Details

Original languageEnglish
Article number024501
JournalJournal of Applied Physics
Volume117
Issue number2
Early online date9 Jan 2015
Publication statusE-pub ahead of print - 9 Jan 2015

ASJC Scopus subject areas