Facile fabrication of suspended as-grown carbon nanotube devices

A simple scalable scheme is reported for fabricating suspended carbon nanotube field effect transistors (CNT-FETs) without exposing pristine as-grown carbon nanotubes to subsequent chemical processing. Versatility and ease of the technique is demonstrated by controlling the density of suspended nanotubes and reproducing devices multiple times on the same electrode set. Suspending the carbon nanotubes results in ambipolar transport behavior with negligible hysteresis. The Hooge's constant of the suspended CNT-FETs (2.6 x 10(-3)) is about 20 times lower than for control CNT-FETs on SiO2 (5.6 x 10(-2)). (C) 2008 American Institute of Physics.