Carbon nanotube field-effect transistors (CNFETs) are fabricated by depositing one bundle of sinole-walled carbon nanotubes (SWNTs) per device between a pair of predefined Pd electrodes using ac dielectrophoresis. By repeating the process for the formation of the Pd electrodes after the bundle deposition, all-around Pd contacts are made to the SWNT bundles. After the formation of all-around contact, the CNFETs with only semiconducting SWNTs in the bundles retain a strong a 106,ate modulation with a high ratio of on to off current I-on/I-off For the CNFETs with at least one metallic SWNT in the bundles, their gate modulation disappears and carbon nanotube resistors (CNRs) are obtained. The on current I-on of CNFETs is found to be sensitive to the process for the formation of all-around contact. In contrast, the two-probe resistance of CNRs is consistently reduced after the all-around contacts. The electrical measurements also indicate the presence of an interlayer residing at the SWNT/Pd contacts. (c) 2006 American Vacuum Society.