High performance of potassium n-doped carbon nanotube field-effect transistors

High performance vertically scaled n-doped carbon nanotubes field effect transistors (CNFET) were fabricated. The potassium doping was used to increase the charge density in the channel and helped to reduce the external resistance in the devices. It was found that the devices showed a tunable threshold voltage in the range of -1.3 V to O.5 V and can carry current up to 5-6 μA. The current enhancement in the devices was achieved by lowering external device resistance due to more intimate contact between K metal and doped nanotube channel.