Vertical connection of carbon nanotubes to silicon at room temperature using a chemical route

The vertical connection of carbon nanotubes (CNTs) to silicon based on a chemical route at room temperature has been realized, using polyethylenimine (PEI) as a binding material between them. Chemical hydrogen bonding and electrostatic interaction between PEI, CNTs, and silicon effectively connect the CNTs to silicon. In this process, CNTs always keep their pristine structure and shape, so the unique physical properties of CNTs are maintained. Electric transport at this junction shows a tunneling behavior, which verifies PEI as a molecular link between CNT tips and the silicon. Control of both interaction and surface termination of the materials at the molecular level allows us to bind the CNTs to the silicon surface without modifying the properties of either.