Electrical measurements of individual semiconducting single-walled carbon nanotubes of various diameters

Individual semiconducting single-walled carbon nanotubes (SWNTs) of various diameters are studied by electrical measurements. Transport through a semiconducting SWNT involves thermal activation at high temperatures, and tunneling through a reverse biased metal–tube junction at low temperatures. Under high bias voltages, current–voltage $\mathrm{(I–V)}$ characteristics of semiconducting SWNTs exhibit pronounced asymmetry with respect to the bias polarity, as a result of local gating. SWNT transistors that mimic conventional p-metal-oxide-semiconductor field-effect transistor with similar $\mathrm{I–V}$ characteristics and high transconductance are enabled.