The secretariat of IEC TC 113 is pleased to announce the publication of Standard IEC TS 62607-6-8 “Nanomanufacturing – Key control characteristics – Part 6-8: Graphene – Sheet resistance: In-line four-point probe”, which provides guidelines for the measurement of graphene sheet resistance using the four-point probe (4PP) method. Graphene, a single layer of carbon atoms arranged in a honeycomb lattice, has gained significant attention due to its exceptional properties, particularly its high electrical conductivity.
With advancements in chemical vapor deposition (CVD) techniques, graphene can now be easily grown and transferred onto large areas, even on roll-to-roll supports, enabling its commercial applications in various electrotechnical products. However, the electrical conductivity of graphene samples can be influenced by factors such as structural quality, contamination, and the physical support used. To ensure reproducibility and assess the electrical properties of graphene, the sheet resistance (RS) serves as a critical control characteristic for this material.
The four-point probe method (4PP) outlined in this standard allows for the measurement of sheet resistance on samples of arbitrary shape, with isotropic conductivity and uniform carrier density. By employing a commercially available dedicated tool, four-terminal resistance measurements are performed, minimizing the impact of contact resistance between graphene and the measurement probes. The method is fast and straightforward, with many commercial fixtures readily available for implementation.
Additionally, the 4PP method provides a certain degree of spatial resolution, depending on the chosen sampling plan to map the sample area. The recently published standard IEC TS 62607-6-8 focuses on the specific application of the 4PP method for chemical vapor deposited graphene on rigid insulating supports. It offers comprehensive guidance on conducting reliable estimations of the sample’s sheet resistance (RS), considering the non-ideal nature of commercial graphene.
Researchers, scientists, and industry professionals involved in graphene research and development, as well as manufacturers of graphene-based products, are encouraged to familiarize themselves with this standard. It serves as an invaluable resource for accurately characterizing graphene’s electrical properties, enabling the advancement of graphene-based technologies across various sectors.
Standard IEC TS 62607-6-8 is now available for purchase. We believe that this publication will significantly contribute to the standardization and widespread adoption of the four-point probe method for graphene sheet resistance measurement, facilitating advancements in graphene-based applications.