CMOS RF noise, scaling, and compact modeling for RFIC design

Abstract

This work presents an analysis of high frequency noise and linearity performance of a 90 nm CMOS process. Measurements are performed for a wide range of nominal gate lengths and bias points at high frequency. Modeling is based on the EKV3 compact model in Spectre RF circuit simulator from Cadence. The model shows correct scalability for noise and linearity accounting for short channel effects (SCEs), such as velocity saturation (VS) and channel length modulation (CLM). Results are presented versus a common measure of channel inversion level, named inversion coefficient. Optimum performance is shown to gradually shift from higher to lower levels of moderate inversion, when scaling from 240 nm to 100 nm. The same trend is observed from investigating the transconductance frequency product (TFP) of a common-source (CS) LNA for technology nodes ranging from 180 nm to 22 nm.