On the Characteristics and Spatial Dependence of Channel Thermal Noise in Nanoscale Metal–Oixde–Semiconductor Field Effect Transistors

Abstract

The physical origin of the channel thermal noise in nanoscale RF metal–oxide–semiconductor field effect transistors (MOSFETs) is characterized based on an analytical noise model, which takes into account velocity saturation, channel length modulation, and carrier heating effect. These short channel effects increase the channel thermal noise compared with predicted noise from long-channel theory. Among the three effects, the channel length modulation is found to be the most important short channel effect on the channel thermal noise modeling. In addition, spatial distribution of the channel thermal noise is analyzed by using impedance field method. From this analysis, it is identified that the channel thermal noise is dominated by source side noise contributions.