Fabrication of back-gated SWNT field-effect transistor by laser chemical vapor deposition

Recent prominent progresses in synthesizing and manipulating single-walled carbon nanotubes (SWNTs) stimulated extensive interests in developing SWNT-based devices for nanoelectronics and nanoelectromechanical systems (NEMS). Thermal chemical vapor deposition (CVD) is one of the most widely accepted technique for growing SWNTs by heating C, the whole chamber and substrate to required reaction temperatures. In this study, we demonstrated a process for position-controllable synthesis of SWNT- FET by bridging the SWNT across pre-defined electrodes using the laser chemical vapor deposition (LCVD) technique. The SWNT-FET was back-gate modulated, showing p-type semiconducting characteristics. The process is very fast and can be conducted using both far-infrared CO2 laser (10.6 mu m) and near-infrared Nd:YAG laser (1064 nm). We have also demonstrated localized synthesis of SWNTs by a focused laser beam. Due to the unique advantages of LCVD process, such as fast and local heating, as well as its potential to select chiralilies during the growing process, it may provide new features and versatilities in the device fabrication.