An Improved RF MOSFET Model Accounting Substrate Coupling Among Terminals

An RF CMOS model incorporating an improved substrate coupling network is developed. The proposed model focuses on characterizing the nonlinear phase of S
₁₂
when a transistor is under zero-bias condition. In addition, a corresponding parameter extraction technique of the model is proposed. To validate this model, a set of transistors fabricated in a commercial 90-nm CMOS process is investigated under multibias conditions. Comparison between measurement and calculation results shows that good agreement has been achieved, which indicates that the proposed model can accurately characterize the performance of transistors up to 66 GHz.