Low energy electron transmission through suspended graphene layers

We measured the transmission of low energy $(< 250$ eV) electrons through suspended graphene membranes. Different number of graphene layers (1, 2 and 5) were characterized using electrons generated from a low voltage Si field emitter array. Biasing the membranes at a different voltage allowed us to control the energy of electrons impinging on the graphene layer. We demonstrate that for electron energies lower than 100 eV, the number of collected electrons even exceeds the number of incident electrons, which could be because of secondary electrons generated in the graphene layers.