An analytical model for the electron mobility limited by surface optical phonons is developed and applied to the simulation of ultra-thin SOI MOSFETs. The developed model reproduces the main features of experimental data recently reported in the literature and has been implemented in a conventional device simulator. An application to the analysis of technological options such as doping concentration and silicon thickness in SOI MOSFETs, is reported. (C) 2003 Elsevier Ltd. All rights reserved.