A blister test for interfacial adhesion of large-scale transferred graphene

A blister test and associated analysis was developed to characterize the interfacial adhesion between graphene and substrates to which it has been transferred. In this study, chemical vapor deposition grown graphene had been transferred to a highly polished copper substrate from its seed foil. The graphene/photoresist composite film was pressurized with deionized water through a nominally 1-mm hole in the copper and the deflection of the membrane was measured by a full field interference method. The deflection profiles compared well with those obtained from a linear plate model that accounted for the initial strain in the membrane and a relaxed boundary condition at the edge of the blister. This was used to calculate the energy release rate as a function of delamination growth to obtain fracture resistance curves for the graphene/copper interface. To the best of our knowledge, these are the first measurements of fracture resistance curves for adhesive interactions between transferred graphene and a copper substrate. The delamination path of the graphene/photoresist sample was confirmed by Raman spectroscopy. The measured adhesion energy for the graphene/copper interface was higher than that of a photoresist/ copper interface, but slightly lower than previous measurements for as-grown graphene on copper foil