Modeling and characterization of radio-frequency characteristics of multi-finger nanometer MOS transistors

This work reports a new model parameter extraction scheme for multi-finger MOS transistors operated in the radio-frequency (RF) range. The drain parasitic inductance, intrinsic capacitance, channel resistance, gate resistance, drain resistance, and source resistance are determined from the scattering parameters measured on RFMOS transistors with channel length of 90nm, 100nm and 110nm with different numbers of gate-fingers. Most of the values and dependencies of the extracted parameters agree with the theoretical models. However, for transistor with gate length of 90 nm and 48 gate fingers, the experimental result suggests the substrate capacitance and substrate resistance should be considered in the small signal equivalent circuit.