3-D modeling of fringing gate capacitance in gate-all-around cylindrical silicon nanowire MOSFETs

In this paper, an analytical model for fringing gate capacitance in gate-all-around cylindrical silicon nanowire MOSFETs (SNWTs) is proposed. The fringing gate capacitances of the SNWT are divided into three parts: sidewall capacitance C_side; parallel capacitance C_gsd; perpendicular capacitance C_gex. Each capacitance is calculated using the following methods: conformal mapping, integral and non-dimensionalization. The proposed model is verified with a three-dimensional field solver, Raphael. Based on the proposed model, the fringing capacitance can be easily predicted in the vertically and horizontally stacked multi-wire SNWTs.