A mobility model including the screening effect in MOS inversion layer

A mobility model for MOSFET device simulation is proposed. The model is not only applicable to both inversion layer and source/drain high concentration regions of a MOSFET, but it also takes into account the screening effect in the inversion layer. The model also includes an improved normal-field dependence for thin gate oxide MOSFETs. The low parallel electric field mobility is estimated by adding mobilities due to donor scattering, acceptor scattering and lattice scattering using Matthiesen's rule. Mobilities due to both the donor and the acceptor scattering include the electron screening effect. The mobility due to lattice scattering is formed as a function of normal electric field E/sub n/, including the strong dependence term of E/sub n/, to express surface roughness scattering. Calculation results of the device simulation using the mobility model show good agreement with the experimental data for various channel dopings. >