Large Area Adhesion Measurements for Graphene Interactions
Kenneth Liechti (), Seung Na (UT Austin), Ji Suk (UT Austin), Rodney Ruoff (UT Austin), Rui Huang (University of Texas at Austin)
Mechanics of Thin Films and Multilayered Structures
Wed 9:00 - 10:30
Salomon 203
Chemical vapor deposition using catalytic metal substrates is a promising production route for large-area graphene. A related issue that will have to be resolved is the transfer of the graphene from the seed metal to the substrate of interest. This is currently achieved by coating the graphene with carrier layer, etching away the seed metal, depositing the graphene on the substrate of interest and removing the carrier layer. Dry transfer techniques based on contact and separation mechanics or delamination are potentially more efficient, allowing for reuse of the seed metal and faster throughput in large scale manufacturing processes. The design and development of transfer processes rely on the measurement of adhesive properties of the various contact pairs involved. The paper describes the development sandwich beam delamination experiments for determining the adhesive energies and associated traction-separation relations of graphene/silicon interfaces. In the sandwich delamination experiments considered here, the graphene was deposited on a silicon strip and the assembly was then sandwiched between silicon beams with polymeric adhesives where necessary. The graphene/silicon interface was delaminated in mode 1 and mixed-mode fracture configurations, complemented by infra-red crack opening interferometry measurements of the normal crack opening displacements. Fracture analyses are then used to extract the traction-separation relations and adhesive energy. Variations in adhesive energy over 45×5 mm regions were correlated to features in SEM micrographs of the separated surfaces as well as Raman spectroscopy profiles.