Analog and RF performance investigation of cylindrical surrounding-gate MOSFET with an analytical pseudo-2D model

We report a systematic, quantitative investigation of analog and RF performance of cylindrical surrounding-gate (SRG) silicon MOSFET. To derive the model, a pseudo-two-dimensional (2-D) approach applying Gauss’s law in the channel region is extended for the cylindrical SRG MOSFET. Based on surface potential approach, expressions of drain current and differential capacitances are obtained analytically. Analog/RF figures of merit of SRG MOSFET are studied, including transconductance efficiency gm/Id, intrinsic gain, output resistance, cutoff frequency fT, maximum oscillation frequency fmax and gain bandwidth product GBW. The trends related to their variations along the downscaling of dimension are provided. In order to validate our model, the modeled predictions have been extensively compared with the simulated characteristics obtained from the ATLAS device simulator and a nice agreement is observed with a wide range of geometrical parameters.