We report a novel resist-assisted dielectrophoresis method for single-walled carbon nanotube (SWCNT) assembly. It provides nanoscale control of the location, density, orientation and shape of individual SWCNTs. Sub-50 nm accuracy and a yield higher than 85% have been achieved. Using the method, we demonstrate suspended-body SWCNT field-effect transistors (FETs) with back-gate and sub-100 nm air-gap lateral-gate configurations. The suspended-body SWCNT FETs show excellent electrical characteristics with I-on/I-off similar to 10(7), ultra-low off currents similar to 10(-14) A and small subthreshold swings. The technique contributes to the ultimate solution for bottom-up fabrication of a broad field of CNT-based devices, such as: complementary metal-oxide-semiconductor and nano-electrical-mechanical-system devices for sensing and radio-frequency applications. Moreover, the versatile method could be applied to the assembly of many other promising materials, such as: nanowires and graphene flakes. (C) 2011 Elsevier Ltd. All rights reserved.