Fabrication and Characterization of Peapod Field-Effect Transistors Using Peapods Synthesized Directly on Si Substrate

We have successfully fabricated carbon nanopeapod field-effect transistors (FETs) using peapods synthesized directly on a SiO 2 /Si substrate. Single-walled carbon nanotubes (SWNTs) for pods were synthesized on the substrate by utilizing position-controlled chemical vapor deposition. The end caps of the SWNTs were removed by oxidation by baking in air. Insertion of fullerenes into the cap-opened SWNTs was performed by the vapor phase doping method. Fabricated Gd@C 82 peapod FETs showed ambipolar characteristics. We have estimated the bandgap of the Gd@C 82 peapod to be ∼100 meV from the temperature dependence of the drain current.