A study of subthreshold behavior of short-channel junctionless cylindrical surrounding-gate MOSFETs from an electrostatic potential viewpoint

Abstract

An analytical electrostatic potential model for Junctionless Cylindrical Surrounding-Gate (JLCSG) MOSFETs was developed by solving the 2-D Poisson equation based on a method of series expansion similar to Green's function. Subthreshold behavior was studied in detail by changing different device parameters and bias conditions, including doping concentration, channel thickness, gate length, gate oxide thickness, drain voltage, and gate voltage. The calculated results of the analytical models are consistent with those of a 3-D numerical simulator without any fitting parameters for various device parameters and bias conditions. This analytical model can be used to investigate the operating mechanisms of nanoscale JLCSG MOSFETs and to optimize their device performance.