A new model is proposed to describe the electron mobility enhancement in strained Si MOSFETs inversion layers using the variational wave functions in the triangular potential approximation. Phonon scattering and surface roughness scattering are included in this model and electron mobility enhancements due to the suppression of these two scatterings are accounted for, respectively. A process-dependent interface parameter is introduced to fit with various technologies. Results from the model show good agreement with experiments for different Ge mole fractions and for a wide range of vertical effective field and temperature. The model is very interesting for implementation in conventional device simulators. (c) 2008 Elsevier Ltd. All rights reserved.