Fabrication and Characterization of Carbon Nanotube Field-Effect Transistors Using Ferromagnetic Electrodes with Different Coercivities

We have succeeded in fabricating source and drain structures of carbon nanotube field-effect transistors (FETs) using ferromagnetic electrodes with different coercive fields. The electrodes were successfully bridged with single-walled carbon nanotubes (SWNTs) by a direct growth method. We investigated the magnetic properties of electrodes and FET characteristics. The magnetic properties of the electrodes survived the chemical vapor deposition process at up to 800 °C, and were found to be qualitatively preserved even at growth times of 20 and 30 min. In addition, the devices showed good field-effect modulation in conductivity. This device structure could be applied to carbon nanotube spintronics devices fabricated by a direct growth method.