Refined Analysis of the Correlated Carrier Number and Mobility Fluctuations Mechanism in MOSFETs

In this article, it is proven that in the framework of carrier number fluctuation mechanism, the input referred voltage noise is equal to the flat-band voltage noise only if the access resistances give a negligible contribution to the total device resistance. The expression of the correlated carrier number and mobility fluctuations (CNF/CMF) noise is revisited, and compact analytical equations are proposed. It is demonstrated that if the degradation of the intrinsic mobility in strong inversion is not too significant, considering a constant intrinsic Coulomb scattering coefficient or a constant intrinsic effective Coulomb scattering coefficient leads to similar extracted noise parameters. It is also proven that a constant extrinsic effective Coulomb scattering coefficient is physically incorrect if the access resistances impact cannot be neglected in the total device resistance.