A new lossy substrate de-embedding method for sub-100 nm RF CMOS noise extraction and modeling

A new equivalent circuit method is proposed in this paper to de-embed the lossy substrate and lossy pads´ parasitics from the measured RF noise of multifinger MOSFETs with aggressive gate length scaling down to 80 nm. A new RLC network model is subsequently developed to simulate the lossy substrate and lossy pad effect. Good agreement has been realized between the measurement and simulation in terms of S-parameters and four noise parameters, NF_min (minimum noise figure), R_n (noise resistance), Re(Y_sopt), and Im(Y_sopt) for the sub-100-nm RF nMOS devices. The intrinsic NF_min extracted by the new de-embedding method reveal that NF_min at 10 GHz can be suppressed to below 0.8 dB for the 80-nm nMOS attributed to the advancement of f_T to 100-GHz level and the effectively reduced gate resistance by multifinger structure.