This paper fabricated SOI nMOSFETs with floating body and different body-contact structures, including H-gate (HG), body-tied-to-source (BTS), and low-barrier-body-contact (LBBC), on the same SOI substrate. Through direct comparison of DC, analog, RF, and noise behaviors among these devices, the LBBC device has been found to show the best capability to suppress floating-body effects, superior output resistance, and low frequency noise characteristics. Although peak values of transconductance and cutoff frequency in the LBBC device are not so high as those in the HG or BTS device, weaker dependency on gate bias in the LBBC device makes choosing of work point more easy and flexible. Among these structures, the LBBC body contact structure could be a good candidate suitable to SOI nMOSFETs for analog/RF applications. (C) 2012 Elsevier Ltd. All rights reserved.