Nanofabrication — Key Control Characteristics — Part 6-4: Graphene — Measurement of Surface Conductivity Using Resonant Cavities

This standard establishes a method for determining the surface conductivity of two-dimensional (2D) single- or multi-atomic-layer thin nano-carbon graphene structures. They are synthesized by chemical vapor deposition (CVD), epitaxially grown on silicon carbide (SiC) substrates, obtained from reduced graphene oxide (rGO), or mechanically exfoliated from graphite [3]. ]. Measurements are made in a standard air-filled R100 rectangular waveguide structure at one of the resonant frequency modes — typically 7 GHz — [4]. The measurement of the surface conductivity by the resonant cavity is related to detecting the shift of the resonant frequency and the change of the quality factor before and after inserting the sample into the resonance, as a quantitative correlation with the sample surface area. This measurement is not directly related to the thickness of the nano-carbon layer. It is not necessary to know the thickness of the specimen, but assume that the lateral dimensions are uniform over the area of ​​the specimen.