We present an experimental analysis of Schottky-barrier metal-oxide-semiconductor field effect transistors (SBMOSFETs) fabricated on ultrathin body silicon-on-insulator substrates with a steep junction by the dopant implantation into the silicide process.The subthreshold swing of such SB-MOSFETs reaches 69mV/dec.Emphasis is placed on the capacitance-voltage analysis of p-type SB-MOSFETs.According to the measurements of gate-to-source capacitance Cgs with respect to Vgs at various Vds,we find that a maximum occurs at the accumulation regime due to the most imbalanced charge distribution along the channel.At each Cgs peak,the difference between Vgs and Vds is equal to the Schottky barrier height (SBH) for NiSi2 on highly doped silicon,which indicates that the critical condition of channel pinching off is related with SBH for source/drain on channel.The SBH for NiSi2 on highly doped silicon can affect the pinch-off voltage and the saturation current of SB-MOSFETs.