Room Temperature Single Electron Transistor by Local Chemical Modification of Carbon Nanotubes

A single electron transistor that operates at room temperature has been fabricated from single-walled carbon nanotubes by using a mask technique. The quantum dot with a length of ∼10 nm was created within an individual thin nanotube bundle via local chemical modification. Conductance oscillations as a function of gate voltage as well as differential conductance peaks versus bias voltage were observed up to room temperature. The series of conductance peaks is explained by the contribution of discrete energy levels within the modified nanotube segment. Assuming similar capacitive couplings to the source and drain electrode, the level separation is estimated to be Δ E ∼ 38 meV.