Small signal model and efficient parameter extraction technique for deep submicron MOSFETs for RF applications

A new small-signal model for deep submicrometre MOSFETs is proposed for acc urately predicting MOS transistor behaviour up to 15GHz. It is a unified mo del suitable for both baseband and RF simulation and valid in both the trio de and saturation regions. The model is implemented as a macromodel with pa rasitic elements added to the BSIM3v3 core. The BSIM3v3 model is the ideal basis for RF simulations as it consists of an accurate nonquasistatic model and a capacitance model. The parameter extraction methodology is analogous to the 'divide and conquer' strategy used in computer science. This approa ch is superior to the traditional method of optimising the entire model to fit the measured S-parameters. It has shown an increase in accuracy and opt imisation speed while reducing convergence problems caused by global optimi sation. Excellent agreement between measured and simulated S-parameters at different biasing conditions in the range from 50MHz to 15GHz has been obta ined.