Investigation of electrically induced migration of copper on graphene surfaces: Theory and experiments

We study the physical adsorption of copper (Cu) atoms onto a graphene surface and their movement along an electric field (F) for a single Cu atom or cluster of Cu atoms using density functional theory. The increasing F can be used to overcome physical adsorption Van der Waals force to drive the movement of Cu atoms, rearrange charges in the system and create a fresh balance in which Cu atoms are trapped in other positions. Experiments confirm calculations of Cu atoms moving on graphene. Both calculations and experiments indicate potential reliability issues of the Cu/graphene contact for nanoscale graphene devices.